Trap medal and altars

[Holywhippet]

One of the possible medals is awarded after using enough traps on the enemy from what I can see. What traps is it talking about? I've used the trap spell quite a few times but it doesn't increase the count.

Also, my dragon can dig for treasure twice in any given combat. If I level up that ability one more time it says he can search for a single altar as well. Is this like those altars that appear on the battlefield that dish out healing/damage? Is it worth it?