In no particular order as I remember them...
1) Unless a power or item specifically states that it does something after a charge attack, a charge ends your turn. This means you can't use a free action after a charge, but, if you have something that is an immediate reaction and it is triggered by the charge, you can use it because immediate reactions don't have to be part of your turn.
2) Charging is a standard action, and as part of it, you have to move at least 2 squares. You can move, run, teleport, etc. as a move action prior to moving these two squares when charging. You can move up to your standard movement rate as part of the charge action.
4) The movement that is part of the charge has to put you in the space closest to your enemy from your starting position. You can use your move action to run circles around your enemy, but your charge action must essentially end in the space you can attack the enemy that was nearest your starting position. If that space is occupied you CAN'T CHARGE.
6) Every rule to charging has an exception granted by a power, feat, item, etc. Watch out for those.
7) Unless a power, feat, item, etc. lets you do something else, the attack at the end of a charge is a Basic Attack or a Bull Rush.
Ah, who figured such a simple mechanic could cause so much fuss? So a few questions:
1. If a charge has to be directly to the target, you can't zig zag? It has to be a direct straight charge?
2. Can I use my move action to position myself by moving horizontally or even away from the target then charge?
How about if I am around a corner and have already used my move action. I cannot charge? (What defines "directly"?)
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(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.