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The Piranha has probably suffered more changes in 5th then any other Tau unit. With this in mind I thought an article would be appropriate. So lets take a look at the Piranha in detail and what 5th means for it.
The basic overview
The Piranha is a fast skimmer, in movement terms this means the following:
(a) A maximum movement of 24" when moving flat out
(b) Can shoot all its weapons at all speeds up to and including combat speed (6")
(c) Can shoot 1 weapon at cruising speed (6" to 12")
(d) Cannot shoot any weapons when moving flat out
If the Piranha moved flat out and is not immobalised it gains a 4+ cover save, however this cover save is only effective against shooting attacks and not close combat attacks. This needs remembering if you move Piranhas down field in the opponent’s territory.
The biggest change for skimmers in 5th is the fact that if they did not move flat out and are immobalised then they are no longer immediately destroyed (this is not the case for squadrons, I will discuss these later). Now individual Piranhas are simply treated the same way as any other vehicle.
Seeing as we are talking about shooting and assault damage here would be a good place to discuss the rules for squadrons.
Squadron rules and their implications
If you are going to use Piranhas you will need an intimate and indepth knowledge of the squadron rules.
First of all I will state the obvious, for a squadron 'you need more than one vehicle'. The following squadron rules DO NOT apply to single Piranhas. If a Piranha is taken individually then all the normal damage rules for skimmers apply.
Ok so you take three Piranhas and they get shot at, what happens next?
Well first of all lets consider line of sight and range. If a squadron is targeted and all the vehicles are facing the shooting unit with the same armour facing then the hits are resolved at that AV value. However and this is a big however, if the vehicles are presenting differing AV values then the AV value of the closest vehicle is used to resolve the hits against all the vehicles. I have highlighted that phrase because it needs remembering because if you are unfortunate enough to leave the closest Piranha to the enemy with its rear or side armour facing the enemy unit then all the vehicles are going to be resolving hits at AV10.
The problem of squadrons and damage
Next we come to the armour penetration rolls. Allocation of damage results against squadrons are treated exactly the same as per allocation of wounds against infantry units. This is probably the worse thing 5th has brought to the table for the Piranha, why? Well because even if only one member of a squadron is in range and line of sight then ALL the members of the squadron are eligible to be allocated damage results. So even if the rest of the squadron is out of sight behind buildings or out of weapons range they will still have to be allocated hits and roll on the damage table.
So if your squadron of three Piranhas takes 6 hits on the one Piranha in range and LOS and three penetrating results are achieved then each vehicle takes one each. So it is quite possible to lose all three vehicles. It does not stop there though, if any of the damage results ends up with an immobalised result then the Piranha is immediately destroyed.
All damage rolls taken against Piranhas have +1 added to them, so a a weapon destroyed for instance would become an immobalised result and therefore the Piranha would be destroyed. Like I said not good!
Stunned results are knocked down to shaken though, which actually is not as good as it sounds, yes the Piranha can move away but it loses a turn of shooting.
One of the main problems with damage results against the Piranha squadron is the fact that any damage results in an inability to shoot. If the result is stunned then it gets downgraded to shaken and it cannot shoot, if it is immobalised it is destroyed and weapon destroyed is not good on a vehicle that has one weapon (I will discuss the problem of Drones and weapon destroyed later). This inability to shoot when damaged severely restricts the Piranhas usefulness.
Cover saves can be taken against any hits as normal, however members of the squadron cannot be used as cover for another member of the same squadron.
Gun Drones and squadrons
When a squadron of Piranhas has Gun Drones they must all disembark at the same time, you cannot disembark Drones from individual Piranhas within a squadron. If the Piranha is destroyed the Gun Drones are treated as passengers bailing out but any hits inflicted on them are resolved at STR3, however remember if only one vehicle is destroyed and its Drones are forced to disembark all the other Drones in the squadron must disembark. All the Drones form one unit and are classed as a non-scoring Gun Drone squadron.
Armour values the truth
The Piranha is an open topped fast skimmer, it is relatively low armoured with an AV of 10 on three sides. This poor AV allied to its open topped status makes it extremely vulnerable to any weapon of STR4 and over. It is not all doom and gloom though the front AV is proof against most infantry weapons (beware when playing against Tau though as the pulse rifle/carbine and Burst cannons can all beat the front AV).
If you are going to use the Piranha you need to ensure that the front AV is the only AV the opponent can trace line of sight to, obviously this is not easy to achieve when your opponent has multiple units of his own. Again we come to the problem of squadrons, if care is not taken when manoeuvring a squadron then you can have all the members taking hits resolved on AV10 because you did not take into account that infantry unit with its 'ineffectual' (or so you thought) weapons that is drawing a LOS to your side armour. I simply cannot stress enough how important it is to ensure you have considered every possible LOS to your squadron before you move it. You will hear the same old thing said about Piranhas again and again "Piranhas are immune to infantry weapons" this is simply not true and this single fact needs recognising. Yes if you can consistently ensure the frontal armour is presented then fine but it is not easy to do and you should be under no illusions that it is very easy to gain LOS on the 75% of a vehicle that has poor armour.
And it gets worse
The new rules have also dealt another blow to the Piranha (and all vehicles), when a vehicle is assaulted all attacks are resolved on the rear armour. This however is compounded even further by the fact that damage allocation is done exactly the same as per shooting. This means that all successful hits are resolved against the squadron as a whole, which means that you can lose a whole squadron easily. Even if only one vehicle is contacted the damage has to be spread throughout the squadron.
If you are going to attempt to intercept a unit by blocking it and you are pretty sure you will get assaulted then make sure you move at a minimum of combat speed and if possible cruising speed; this is to ensure that at least a 4+ is needed to hit the vehicles when assaulted and give them a fighting chance of surviving (a 6+ is needed to hit a vehicle that moved at cruising speed and over).
The Piranha comes equipped as standard with a Burst cannon and two Gun Drones. Not it must be said the most fearsome array of firepower. The Burst cannon and Drones only have a range of 18" and are basically only any good against infantry and low AV (11 max) armour/vehicles (though it must be said if you can draw LOS to lower AV10 rear armour the BC and Drones are effective).
The average BS of the Piranha exasperates the fire power problem even further because the three shots of the BC means an average hit rate of 1.5 which means a very very poor casualty rate amongst any unit it targets. The Drones are a little bit better as they have twin linked carbines and can (if lucky) pin units; however the Drones will more than likely be disembarked quite quickly.
So really the Burst cannon is not much of an option, luckily we have an upgrade option, the Fusion blaster. The Fusion offers vastly superior strength and an AP of 1 it can destroy anything it hits.
Surprise surprise though the Fusion does have downsides, the main one being its range. Fusion blasters have a range of 12" and need to be at 6" to be sure of a damage result. When you the ally the iffy damage potential to the 50% miss rate for hits it means it is a far from certain thing that a Piranha is going to be successful when used to kill high AV vehicles (which it must be said is one of its most commonly put forward reasons to take it in a list).
So given the fact that the Piranha suffers from a low shot volume and average BS we need to ensure we make the most of the weaponry offered to us. Luckily we have the targeting array as an option and at 5pts it does make sense to utilise it, BS4 is much better and when used with Marker lights a BS of 5 can make all the difference when hitting that tank.
So we have a Piranha with a Fusion blaster, two Gun Drones and a Targeting array for 70pts, which is not to bad. What else do we need? Well given the fact that the Piranha is tissue paper tough we need to make sure it gets every possible chance to survive. Fortunately we as Tau players have been blessed with the Disruption pod, this confers a 4+ save (obscured) to any vehicle that is over 12" away from the shooting unit. Basically this is a MUST HAVE.
Most will agree that this is the optimum build for a Piranha for a cost of 75pts. One other option well worth considering is the Flechette discharger; this is a nice bit of kit that inflicts an automatic wound on a roll of 4+ on a D6 on any model assaulting the vehicle before they roll their attacks. Remember that rule that says that assaults against squadrons are resolved against the squadron as a whole well the good thing is that the reverse of that is if all the vehicles have flechettes then the attacking unit gets hit with multiple flechette hits. So if a squad assaults a three Piranha squadron then the Tau player would roll 18D6, this can mean a lot of hurt for the attacking unit.
Gundrones: a discussion
Piranha’s come as standard with two Gundrones (GD from now on). These GD have a few rules and quirks that need to be understood.
(1) GD’s are passengers! This means that they have a few rules that need to be understood in relation to this:
- They can disembark from the Piranha but may not re-embark.
- They cannot disembark if the vehicle moved flat out
- They can assault after even if the vehicle moved before they disembarked (obviously not if the vehicle moved flat out)
- They must disembark if the vehicle is destroyed and will each take a STR3 hit
- If one Piranha’s Drones disembark all the squadrons Drones must do so at the same time and form a unit of Drones
Now we come to something that is not widely known, GD’s are not eligible for removal due to a weapon destroyed damage result. Don’t believe me then check the rules for GD’s in the vehicle armoury; it says that GD’s are treated as passengers if the vehicle is damaged. Now check page 67 in the main rule book under the heading ‘Effects of damage results on passengers’ the weapon destroyed section says that this result has no effect on passengers, so we cannot remove the GD.
Now to restate the obvious a damage result is damage and the codex clearly states that if the vehicle is damaged then the GD’s are treated as passengers. This is not good for the Piranha because as soon as its main weapon is destroyed from then on any weapon removed result means the vehicle is immobalised, if it gets another weapon removed result and is still immobalised then it is destroyed. We also need to remember that a piranha in a squadron that is immobalised is instantly destroyed.
(2) GD’s fire as a part of the vehicle but use their own BS, they cannot fire if the Piranha is stunned or shaken.
(3) Even though disembarked GD’s form a unit they are never classed as a scoring unit.
(4) Each GD unit counts for one kill point if destroyed. You need to remember this if taking multiple individual Piranha’s, if you take three that is a potential three extra kill points for the opponent and that can tip a game.
Uses for the Piranha
Ok so we have discussed the Piranha in depth now we need to work out how best to use them. Now we can use the Piranha in two ways:
(1) As an individual unit
(2) As a squadron between 2 and 5 strong
Each of the above have positives and negatives, so let us discuss them.
The individual Piranha
Well the main strengths of an individual unit are:
- Immobalised results do not destroy them, the individual Piranha is treated as a standard skimmer for the purposes of damage resolution
- An individual Piranha is a lot easier to hide and it is also easier to ensure its front armour is presented to the enemy
Well the obvious disadvantage is a lack of firepower. It cannot be denied that even with a Fusion blaster and a targeting array the Piranha is only putting out one BS4 shot. The Drones if not disembarked offer two more shots but even then the offensive power is hardly inspiring for something that costs 75pts on average.
With these points in mind we need to assess what the best use for the individual Piranha. Well given the fact that it is going to be pretty hard to ensure that anything hit by the Piranha is going to die or be destroyed we have to think of it as a more tactical unit.
A lot of missions in 5th rely on troops controlling objectives and a Piranha can contest objectives if it is within 3”.
The best way to achieve this is to take a single Piranha with Disruption pods, Burst cannon and Drones. Do not disembark the Drones during the game. Ensure the Piranha is kept hidden or as far away from the action as possible. (If needed you can shoot with the BC and Drones but make sure you do so at maximum range as this gives the Disruption pod a chance to protect the Piranha).
It is best to keep away however and ensure the Piranha is around for the last turn.
You can either stay at maximum range and boost towards the objective and rely on the 4+ save to ensure a bit of survivability if the opponent has a turn left. Or you can manoeuvre so you only have to move 12”in the last turn and then move the Piranha to within 3”and disembark the Drones. This means the opponent has to deal with two units contesting the objective. If the opponent has a turn left then you can assault the unit on the objective with the Drones and have the possibility of keeping the unit in assault and thus prevent your Piranha getting shot at in the last turn.
Either way the Drones are handy to have around and should be disembarked when the Piranha is used to contest an objective.
Of course if it is you that has the last turn then simply just move within three inches and contest the objective. The Burst cannon is taken because it is better to have shot volume when shooting at units in cover (units on objectives are usually in cover)
Another use for the individual Piranha is as lone armour, tough unit hunter. This is not the best use for an individual Piranha; however a lone vehicle is often overlooked and can take an opponent by surprise. In my opinion the best set up is Fusion blaster, Targeting array, Disruption pod and 2 Seeker missiles.
Depending on scenario, opponent deployment etc the Piranha can be used several different ways.
- As a fast flanking Seeker missile delivery platform. Deploy the Piranha on a flank and in the first turn movement phase boost it straight down the flank. The Piranha gains a 4+ cover save and hopefully will have line of sight to a target. If you have deployed sensibly you will have a marker light trained on the target and the Piranha can send a Seeker to the target on the side or if lucky rear armour. This can be a useful tactic to shift targets at the rear of the field.
The thing to watch out for with this tactic is the fact that you will inevitably be moving the Piranha into enemy territory and therefore within range of the opponents weaponry. It is best to try to get the Piranha into some sort of cover , luckily Seekers do not need LOS to hit and have unlimited range so you can select the best place to move the Piranha to so you can utilise the best available cover.
- As a Dreadnought, Sentinal or similar hunter. The Piranha has the advantage of being fast; this means that it can manoeuvre to gain LOS to rear armour and even the Pulse carbine of the Drones can beat low AV. Even if it does not gain LOS to rear armour the Fusion is easily capable of penetrating the armour of a standard Dreadnought and damaging it (if you are lucky even destroying it). The Piranha is very well suited to hunting the slower walkers. Seekers can be taken for this role as they can offer another level of firepower and even allow one Dread to be targeted with the Fusion while hitting another with the Seekers. If one Dread is destroyed the Piranha has made its points back.
- If you are considering using the Piranha to hunt things like Independent characters or Monstrous creatures then you must remember its firepower limitations. It is best to hit targets that can be insta killed and this limits the targets to toughness 4 maximum. Luckily there are plenty of characters with this level of toughness or even less. It is best to use the Piranha as a support unit when taking down MC’s. Obviously the Fusion is best used here.
- Another tip is to disembark the Drones when confronting Independent characters or MC’S. Disembarking them in the movement phase and placing them between the Piranha and the target means that if the target survives the Drones can assault and hopefully allow the Piranha to escape. You can also just leave the Drones (do not assault) because the opponents unit will have to move around them to get to the Piranha and hopefully will not have the range to do so.
- The reserves rule is very useful for the lone Piranha. When used in conjunction with a Positional relay equipped model It can be used to keep a Piranha safe until it is needed to contest objectives. If you take multiple individual Piranhas then you can bring them on when it best suits in the later half of the game. Remember you can be assured that even if the reserves rolls do not go to plan then the Piranhas still arrive in turn five which gives you plenty of time to manoeuvre in to position.
First things first, forget about the full strength Piranha squad. It is simply too expensive, to unwieldy and is way to vulnerable to the conditions I described earlier regarding LOS avoidance problems and dispersal of damage results through the squadron. Two or three vehicle squadrons are advisable but three is the absolute maximum.
Advantages and disadvantages of the squadron formation
One advantage is obvious, more offensive impact. Three Piranhas with Fusions and targeting arrays can be assured of damaging pretty much anything they hit. Maximise this potential by taking targeting arrays, Fusions and utilise any Marker lights available.
Errrr that is pretty much it for advantages , I suppose the fact that you can get a 6 man Drone squadron from three Piranhas is also pretty good.
The disadvantages well first of all if you are going to use a squadron then you have to be extremely careful when using them. A three-vehicle unit is a large target and it is going to be extremely hard to keep them from drawing fire. Also three optimally equipped Piranhas will cost around the 220pt mark and this is going to take some earning back. I have already discussed the problems associated with damage dispersal and other problems such as vulnerability to assault, so lets see how we can at least lessen these problems.
Ok so it has been established that simply rushing up the field with a squadron of Piranhas is foolhardy and will more than likely result in the loss of the squadron (or members of it at minimum). With this in mind we need to think about their role. A Piranha can move 12” and still fire its main weapon this makes it a very good unit for intercepting units. What comes to mind here is intercepting transport vehicles that are bringing units close to your lines or objectives, keep the squadron close to your lines/objectives and send them out to intercept when needed. When you are intercepting transports it is wise to disembark the Drones in the movement phase as these can be used to shoot any passengers that are forced to disembark and if needed they can assault as well, this is important, as with luck it will prevent the passengers from shooting at the now exposed Piranhas.
Obviously transports are not the only targets open to this tactic; however be extremely careful when attacking units like bikes or Ork trukks as these units can be surprisingly resilient and of course can shoot back.
If Marker lights are available then use them to up the BS of the Piranha squadron and if possible to down grade any cover save the target has acquired. You need to really maximise shooting with Piranhas to avoid any retaliation.
The screen tactic
A use much espoused is the skimmer screen, this used to be an effective tactic but 5th has really made this tactic less effective. The screen is usually used to prevent movement to another unit or portion of the field. If you are using the Piranhas to screen against shooting then you must ensure the frontal armour is the only armour the opponent can draw LOS too AND you have decoys. This will at least ensure the squadron has the best chance of surviving the shooting. If you are using three Piranhas the best way to prevent LOS to side and rear armour is to place the Piranhas in a half circle with the front of the vehicles facing outwards and the tails of the vehicles nearly touching each other, this ensures that the maximum area of the side and rear armour is protected and that any enemy in an 180 degree arc is presented with the frontal armour.
Assaults are even worse for Piranha squadrons for the reasons discussed earlier. First to have any chance of surviving an assault unscathed taking flechettes is paramount. Second Drones are essential, so if you are sure you are going to use the squadron for a screening tactic do not disembark the Drones until you need to, they are safer on the Piranha. When you set up the screen disembark the Drones and have them set up in front of the Piranha squadron, these will provide a buffer and Drones are surprisingly effective in an assault situation. For a screen to be truly effective the Drones must be utilised in this fashion and flechettes taken, any unit surviving the shooting from a squadron of Piranhas, Drones, assault from a Drone squadron and the flechettes deserves to do well.
Squadrons can be used to hunt things like Independent characters and multiple wound Monstrous creatures. However you need to be careful, IC’s and MC’s are tough targets and you need to approach targeting them with care. Obviously Fusions are the weapon of choice with their strength and AP and again Drones and flechettes are your friends. Make sure the Drones are placed to prevent an assault from the character if it survives the shooting and the flechettes will at least have a chance of damaging the character if it does get into assault.
The 12” move of the Piranha can also be used to catch out an opponent. Use a unit as a lure (possibly Kroot or a unit of Fire Warriors) and have the Piranhas move in to trap the unit in a crossfire. Care needs to be taken though to ensure that you are not presenting the squadron to fire from units with longer ranged weapons or vehicles. This tactic is useful in hybrid lists with static elements in the army to use as lures and the squadron can be used to defend objectives.
The best option
All things considered I think the single Piranha is the better option for a Tau list. It does not suffer from the disadvantages presented by the squadron rules, it is easier to hide and losing one is not such a problem. In fact taking two or three individual Piranhas is probably the optimum set up. Utilising the reserve rules can be useful and can really give the opponent a headache because he has to take into account the fact that two or three fast moving units are going to be arriving at some point. Taking single Piranhas also means it is feasible to use one as a sacrificial speed bump or to use one as a suicide attack unit against armour simply because you are only losing 75pts and not 200 plus points. Squadrons simply have to many disadvantages under the rules in the 5th edition to make them a worthwhile edition, unless you are totally aware of all those disadvantages and are aware of just how careful you need to be using them.
I have tried to give an honest and in depth appraisal of the Piranha in this article and I am sure that many will see it as a negative appraisal. This is not the case I have tried to cover every single angle regarding the Piranha to allow players to be aware of what is needed to play them well. I hope it helps anyone who is wanting to play the unit.
Last edited by Rikimaru; November 18th, 2008 at 16:07.
Mate, Nice work. very in depth and thought provoking! I vote it be pinned.
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I dont know if i misread or skipped over the part you mentioned this but if you have a lone piranha thats 2 kill points 1 for he piranaha one for the drones 3 individual piranahs are 6 points but 3 piranhas in one squadron is 4 kill points.
Most people think piranhas ar enot worth it but i suggest everyone trie sthem out as everything is on an individual basis and i would hate to see monotone Tau lists that are threating to appear. 2 commanders 6-9 elite battlesuits 0 or full squad of stealths 4 units of firewarriors 2 units of kroot 2-3 units of path finders 3 hammerheads. i hope this is not what Tau become.
Hah I mention the response thing and lo and behold one appears literally while I am typing it.
160 that is an excellent point, if you take three lone Piranhas you do indeed risk losing 6 kill points. Drones have to disembark if the vehicle is destroyed and then form a unit (if they survive) this unit is then worth a kill point if destroyed.
Squadrons disembark all Drones at the same time and thus form only one Drone unit (worth one kill point). However I must stress that taking lone Piranhas will extend their survivability due to easier utilisation of cover and no squadron damage rules. I think I would rather take two lone Piranhas over a squadron (of say three). You could still co-ordinate the fire from two Piranhas while avoiding the pesky squadron disadvantages. There you go! another idea on how to use the Piranha and avoid its disadvantages, use two and co-ordinate them rather then taking them in a squadron. Of course this does take up two fast attack slots but nothings perfect.
On a side note I want to point out that this is NOT a way to get into another slanging match RE Piranhas, I want this to be positive, so c'mon contribute.
Last edited by Rikimaru; November 18th, 2008 at 21:24.
Hmm its hard to be positive, i think my main problem with them is they can be replaced in most of their roles, there not neccessarily overy bad but they do not fill a niche other than as a last minute contestor.
I think we have to eliminate what others units can do better at then see whats left. they are the only unit to have a 27" contetsing range.
Burst cannon Piranhas are to me the least worth it out of all as they to my mind arent better than stealth suits. although they can start from further away the JSJ suits have the advantage on most enemy firing back. Also you get 2 stealthsuits to 1 piranha
Ill add more to the disccussion when im more awake
Nice work riki.
I've used pirahna in my last few games and found them invaluable. One item I would like to include is the new reserve rules in the missions. They allow you to keep any unit in reserve in any mission.
I have been using the fusion/TA/DP setup with two solo pirahna and kept them in reserve. Almost every single army in the game wants to close with Tau to finish them off and need to move things around to capture and contest objectives. The fast move of the pirahna has allowed me to get close to dreadies (insert other nasty vehicle/MC) closing in on my army and deal with it without worrying if my little skimmer will get shot before it gets to shoot.
So far they have destroyed many times their own points in vehicles and taken the last wound off a daemon prince. The later insertion of the unit means your opponent is forced to react to this new threat and can change their battleplan. It also aids in preserving the little fella's for an objective grab.
In essence I think the bigest change for pirahna in the edition change is not a change to the vehicle rules but the change to the mission rules. It has given the pirhana a great boost in my opinion.
ps: I'd rep you riki but I have to spread the love around a bit first.
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still not convinced to spend £15 on one, for dedicated tank "tank must die" unit I've always loved a deep striking suit with TL FB and drones, excellent post nontheless.
I can imagine one being useful though to take vanilla so it draws little to no attention and then use in turn 6 6 to whoosh across the board and contest an objective
less hate more kittens
Having to deploy on your board edge is no problem because of the Piranhas speed. Having the option to deploy later in the game really helps the Piranha because units will be spread around the field and many of the opponents units will be reduced in strength or things like tanks will be damaged and ripe for picking of.
The single biggest advantage though is that with some planning you can keep the Piranha of the table, safe and in one piece until turn 5 and then get it on the table to contest objectives. This is quite literally a game winner. If you have two Piranhas in reserve, contesting two objectives can easily tip the game your way.
I guess you have to look at the Piranha more as a tactical weapon and not an offensive weapon because lets be honest here the Piranha is not the best offensive weapon in the Tau arsenal but with some thought and some hard analysis of the new game structure then I think uses can be found and that has got to be good.
Last edited by Rikimaru; November 19th, 2008 at 00:38.
A couple of things, Rikki:The rules say that it's the vehicle which is being attacked is able to release the FDs against the attacker. It doesn't mention anything about the rest of the squadron being allowed to do so if only one of the vehicles is being attacked. That's the anomaly with the Assaulting Squadrons rule - the attackers do get to smack at everything in the squadron even if they are not in BtB or engaged with each vehicle. The FD rules don't say that if one vehicle in the quadron is attacked then the entire squadron can let rip with their FDs.Remember that rule that says that assaults against squadrons are resolved against the squadron as a whole well the good thing is that the reverse of that is if all the vehicles have flechettes then the attacking unit gets hit with multiple flechette hits. So if a squad assaults a three Piranha squadron then the Tau player would roll 18D6, this can mean a lot of hurt for the attacking unit.The drawback with the Pos Rel is that if you elect *not* to use it, then you MUST roll to see if those Piranhas turn up or not. If however you elect to use it, then you are denying yourself everything else that is in Reserve. To retain the Piranhas until Turn 5 means that you would have to keep at least 3 other units in reserve (for Turns 2,3 and 4 reserve rolls) in order to allow you to use the Pos Rel and delay the arrival of the Piranhas.The single biggest advantage though is that with some planning you can keep the Piranha of the table, safe and in one piece until turn 5 and then get it on the table to contest objectives. This is quite literally a game winner. If you have two Piranhas in reserve, contesting two objectives can easily tip the game your way.
As a general comment:
I tend to agree with your assessment that using a single Piranha is probably the best way to contain the amount of damage which can be all too easily inflicted on a larger squadron. 2-man units are probably the most viable success-wise as your firepower is doubled and the Drone squadron when released is of a more significant and effective size.
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Wouldnt you want to bring on piranhas in turn 4 since in turn 5 your limited too half the board unless game continues.