Rules FAQ
-
If the character is unique and there is another copy of it in the dead pile, you cannot put it into play. You also cannot put it into play if a copy of it is in your dead pile, or if a copy of it is already in play under your or its owner's control. (See FAQ.)
-
At the end of the phase, the character is "placed" back in the dead pile. This is different to being "killed", so card abilities that interrupt or react to a character being killed cannot be used.
-
A character can enter the dead pile if it is killed, or by being placed there directly by a card effect (such as Crone of Vaes Dothrak). Warlock of Qarth can react in either of those cases. It can even react to a character being placed in the dead pile by the delayed effect of another copy of Warlock of Qarth. In that case, the timing point of its delayed effect is immediately reached, so the character is placed back in the dead pile before any reactions to entering play (forced or otherwise) can be triggered. For example, if that character is Alester Florent, you will not have time to trigger his reaction to entering play, but you will have time to trigger his interrupt to leaving play.