I'm wondering if I need to pick up skulls that drop or if they will auto-collect at the end of a wave or the level? Mainly because sometimes they aren't in my field of view, and I may not hear the audio queue due to being in the middle of the action around me. Also they may be on the other side of the map during endless when I need to cover an area with minimal time between waves.

2 Answers

If you don't pick up the skull, it doesn't count. It's a pain, but OMD2 is usually kind enough not to make the final mob drop a skull, so do a quick runaround before finalising the map (if you can do so before your traps kill it)

You should pick it up, In fact if you play with a partner and he/she picks up a skull your it won't count for you at the end of the game.

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