| Melanikus |
Glyph of Warding covers a lot of this, with the interesting limitation that you can have only so many glyphs. That doesn't sound entirely reasonable - a wizard with more money than sense should be able to buy them at industrial scale, right? But there's a game balance concern too, hence the limit.
Over the years a variety of game firms have tried to write rules for players making traps, but it turns out to be really hard to write well-balanced rules for that. Because while the GM writing a dungeon is trying to create a fun, reasonably challenging obstacle course, that's not what a player building traps is doing.
A player building traps is trying to win. Ideally, the setup will be as unfair and unbalanced as possible, guaranteeing the destruction of enemies.
I had not even considered Glyph of Warding (although I did try looking up Exploding Runes, to no avail).
I think that this will have to fill the requirements as I really don't want something that they can abuse.
Thanks for your help.