Forgotten Crypt causes all attacking champions to be placed in the discard pile at the end of the round of battle, even if the attacker won the round. Undead are unaffected by this power, and battle ends normally.

Attacking champions that are able to retreat to their pool to escape defeat, such as Erital Kaan-Ipzirel (81/AR), can avoid the power of the Forgotten Crypt by activating their power before the battle is over. This is possible because the Crypt's power does not activate until the battle is over.

Sometimes battle is ended by a means that leaves no clear winner or looser, such as a Wall spell. In these cases the attacking champion is still discarded unless he has someway to escape.

The Forgotten Crypt is usually best placed on your lead realm, since it is the most likely target of attack. This holding becomes even more crueling if you are able to combine it with a realm that is restrictive to attackers like The Coral Kingdom (10/4th). This combo leaves your opponent with few attacking champions to start and can quickly bleed them to the discard pile leaving you free from attack on later turns.

All in all, the Forgotten Crypt is a good holding for a Forgotten Realms theme deck, but is a weak choice in a standard tourney deck. If you are using many low level champions as cannon fodder and have several Forgotten Realms realms in your deck, you may consider this holding, especially if you are using a revenge theme.