Trap Tip 1: Exploding Disengagement

Here is how to use explosion traps properly even prior to getting Trap Launcher at level 12, without exploding yourself:

Disengage. If you start as a Cornac Rogue, you can use your freebie Category point to unlock the tree with Disengage in it, and spend your very first generic point on Disengage. Spend your first two class points on Trap Mastery.

When you've got a whole group of enemies right in front of you, and enough room behind you, lay an explosion trap on your own tile, and then disengage the enemy in front of you. Kaboom. And only the monsters burn!

Note that it's important to make sure before you lay the trap that you have enough stamina for both the trap and the disengage.

Unfortunately, only Cornac rogues really benefit from this technique, since rogues of other races have to wait until level 10 for disengage. It would be so wonderful if rogues started with that tree unlocked already.

Trap Tip 2: Catapult Archery!

When you've got a bunch of enemies coming at you, back into a hallway so they can come only from one direction, and lay a catapult in the opening. Stand behind it with your bow or sling ready. As the enemies approach, they'll be hurled back. While they're being pushed away from you, shoot them. Shoot them until the catapult goes away. Lay another one. Shoot some more! Also fun with wands.