There was no combat. You don't need to be in combat to attack, this isn't a videogame
And who said DM Fiat? Maybe that Troll had a heart condition before hand.
Also traps that split the party or do long term affect wouldn't be "Too high a CR", 3.5 makes use of them all the time (typically a trap that causes no harm gives no exp... The "Bonus exp" would be in the difficulty modifiers for the next encounters). This is ignoring that spells directly apply their circle in CR. HECK most harmless traps aren't intended as a trap, they might be a secret passage that the players blundered into.
But yes I also ignore harmless traps regardless of what the rules say. Disabling a teleportation trap capable of teleporting the entire party into a model replica of the same room isn't going to win you "mass teleport" exp (mostly because it just becomes a bloat). I might give a bit, but you didn't really achieve anything.
Which is kind of a thing... Getting hit by a trap isn't an achievement nor is it a learning experience... at least no more so then the basic exp just for beating an area is.
I mean the trap was built, hidden, and put there to hurt you... and you foil it by... falling for it. Which is exactly what it was trying to do (and MOST traps aren't meant to kill you but weaken you off)
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Then again as I said, I've never ever gotten a single bit of exp for not foiling a trap.
Heck one DM I had basically went the extra mile and if you got hurt by a trap at all... you just flat out don't get the exp regardless if you disable it later or not.
I've never ever heard of until just yesterday of earning exp for basically being a dummy who falls into a pit trap and needs to be roped out. It is the dumbest thing rule wise I ever heard (while Anti-plague is more of a setting issue in being a piece of technology that is outright many times more advanced then a even a renaissance setting would suggest)... It feels like incompetence EXP. No other system I have ever played rewards you for incompetence... At most they give you "Well you tried your best", even if that failure manages to hurt you dearly. The closest I have ever seen are games where there is a pittance reward for "Failing so spectacularly that everyone has a great time".
but then again "EXP for just seeing a trap that exists" is a pathfinder thing. It is the only edition of D20 that does so. But then again Pathfinder is a very "I want to give you full exp no matter what you do" system. So choosing, for example, to bribe the god not to kill the city nets you exp equal to defeating the god. It is probably the worst aspect of Pathfinder now that it has been brought to my attention.
Which means EXP in Pathfinder isn't "Experience" but rather some intangible reward taking out of roleplay and right into "videogame". To say that bribing someone with money you have on hand is the same equivalent learning experience as actually facing them in mortal combat is just flat out abhorrent.
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I know sometimes you have to kind of fudge things
Generally speaking I don't give exp for someone being killed outside of a combat thing... Casting Cloud Kill doesn't net you exp for every person who dies from it after you left the area because you aren't learning from it even if we do it by a move by move thing.
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