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I had a match between Empire, and lose
anyway i have 2 scorpions and 2 misfires ;D and i rolled 3 and 6 so he asked a question could he place the marker under his unit. I dont know the answer
Also at one of my magic phase my Tomb Guards unite declares charge to his swordsmen unite and its detachments did supporting charge, is it legal? i think it is, so we played liked that.
Next question (and I have a decent-sized Empire force, so I know the answer for a fact), and yes, it is legal. The main unit (Parent unit) can have up to two Detachments. Any ranged units can do Stand and Shoot for the Parent unit, and any cc units can do a support charge (an out-of-turn charge). Nasty stuff, it is, assuming they pass their Fear test...
To answer your question about ICFB, If the scorpian scatters are is placed under a unit and arrives in that turn then they count as charging the unit... Does that clear up your confusion?
With the empire generally with their detachments the certain units can have smaller units attached to them and this includes swordmen and greatswords! The two smaller units are allowed to respond to the main unit being charged... hence a hand gunner unit can stand and shoot and units of Halbediers can flank charge you. It is totally nasty, surprisingly I know only a hand full of empire players if even that and only one of them uses detatchments and he smashes a lot of people due to this rule...
There is nothing more annoying when your Wyches with Plasma Grenades get "Always strikes First" for their combat drugs!
If the marker is moved under an enemy unit then the Scorp will charge. The opponant may move it under another unit.