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One word... NO
I'm tired of people saying the casket isn't worth it cause against many armies it wont cause any real damage, in my personal opinion it can cause vastly more damage than a chariot unit with full command ever will, and its phenomenal at scaring your opponent into saving dispel dice for the casket allowing all your little schemes and sneaky movements to work perfectly to plan.
Besides even if your opponent does save all their dispel dice for it, there is no guarantee by any means they will dispel it anyway, and if you roll well you can cause some heavy damage, especially if enemy wizards are hit.
I'm sure lots of you disagree, but most people who use it cant deny its usefulness.
I think many people just don't like the idea of making one of your very important Liche Priests a proverbial sitting duck.
However, I'm new to the game and with Tomb Kings being my first army, I'm seriously considering running a Casket against all of my normal opponents, save Dwarfs, for the very reasons you listed. But ultimately, I think the mileage you'll get out of the Casket is directly related to your Hero/Lord setup.
My first game with TK was 1500 points and I ran TP/LP/LP. As I move towards 2000 points, I'm seriously considering running TK/TP/LP/LP as my staple setup at 2k and I think putting the Casket on the table will initially help me balance out what I'm lacking overtly in the magic phase during the first few turns by potentially eating away dispel scrolls and dice as I line my units up for the attack. Sure I could use 2 SSCs, like everyone else. But I've never been one to follow trends.
Hell, I chose Tomb Kings as my first army after all...although Ogre Kingdoms made that decision hard after I read their army book.
Im not a TK player, but its almost stupid not to field a CoS against most armies.
I have had my Skaven and Empire decimated in just a couple turns from the casket.
There is no down side really, Either its does tons of damage, or the opposing player reserves precious DD for the casket thusly allowing some other spells to go off.
The problem with the casket is not in the damage it causes. The sheer number of unit effects means its always worth it from that angle. The problem with the casket is that its very easy for several armies to neutralise.
Any army that can field a cannon can have it gone by T2 with good guess work because the priest is a sitting duck and the way the casket works means you can't put it behind cover. Granted the demise of DoW means that far fewer armies have access to cannons, which works much in our favour.
Next snipers, there aren't too many of these about, but still fear the welf sniper noble or Empire outrider champ with hochland long rifle.
Lasty template weapons are a big problem. Far less accurate than the cannon, but still dangerous, you can bet that if a template is dropped on the priest he's a gonner, big templates from helstorm rocket batteries or mortar type weapons are a big threat, while even regular stone throwers can be deadly in the hands of a good guesser.
There aren't very many armies that don't have at least one out of those three, and losing the casket with the attached priest really does cripple your magic phase, with 4D6 worth of incants out of the window.
The art of Eldar: Paint clean, play dirty!
U must never forget the -1 to cast the opposing army suffers. U should take it just for that! I mean vampires are now having to cast their rasing on 2 dice to make sure it gets off and even then its still at -1. Ogres spells now need 4s to cast meanying they will need 2 dice as well. It hurts magic heavy armies even if it doesn't cause all the damage u want it to.
But it also depends on what style of play u plan on using because an attack army wont ever need one but it can really work in a defensive list.
I always take a casket, it has yet to be a burden more than a help.
Not to railroad the thread off track but is the casket supposed to target characters AND units? Or by if you get a wizard do you mean if he isn't joined with a unit. I was under the impression that characters joined in a unit weren't targeted separately.
I've played against TK once, and they fielded a casket, and it was a nightmare. I still dominated the magic phase with my Slaan, but it was hard to destroy as with Lizardmen I had no cannons, stone throwers etc. and I wasn't using a Stegadon, but I won still , mainly due to my blocks of Saurus not being that affected by the fear and their skellies were easily destroyed in CC.
But back to topic, if I were a TK player I'd take one every game whoever the opponent.
The Casket is useful, but I'm not a magic crazy guy in WHFB. I feel 1 lord and 3 heroes (five spells) with a Jar is enough for me in the magic phase. I understand many people do like magic heavy and this helps in both offense and defense magic.
So, some people such as myself would rather spend those points on more units. The Casket of SOULS is a good option, but not mandatory by any means. (I mean, some of the army lists on here don't have any chariots which just horrifies me!!! lol)
OH! I might add, that if you bring a casket you can't have TWO SSC .
I can't think of another army that I wouldnt' at least consider fielding it against (since none of our group runs any of the "power armies." Ironically, we run everything but.
The casket can be very useful and becomes more powerful the larger the game. However, at 2000 points i think you're better off with two catapults, they are easily the best thing in the book, and with the power creep of other armies these days you really need them.
The casket can still be very helpful, forcing people to hold back dice or scrolls, thus allowing your other spells through. So definitely not a waste of points, but at the standard 2000pt level, two catapults are your best bet.