If a door or chest trap kills the opener, does the door/chest still open?

McRae said:

Unless the card or Trap says otherwise (ie when the Chest turns into a Beastman and is specifically not counted as open until the Beastman is killed), then yes.

The card cannot be played until the activating condition is complete. Once the activating condition (open door, open chest) is complete, play the card, follow through the effects, and then continue as normal. The rules do not say anywhere that the activating condition sudden ceases to have happened just because the 'activating' hero gets killed. The beastman(/Ogre w Treachery) chest trap card is different because it specifically overrides the normal rules on the card.

Corbon said:

And is a lot of fun on the Reflections level in RtL with all the portals. I had the Heroes running around for like 5 turns trying to chase down the Mimic'd chest.