(Psi)SeveredHead
Adventurer
I have used traps quite a bit in my 13th Age sessions. Here are some examples:
During Encounters
A pool of acid with some invisible "monkey bars" over the top of them was one trap/hazard that worked well, as they needed negotiating during a combat where monsters turned up on both sides of the pool. This simple trap/hazard did damage and made the combat nastier if the players ended on the wrong side ...
Where was the pool in relation to the room, and where were the PCs at encounter start? Did they split up for some reason? Need more detail.