Dungeon Masters Offering Dangerous Gifts

My library game took a twist today. The players are in the Feywild, a realm of wild magic and capricious beings far beyond the forces seen in the usual material plane where most stories occur. Their last session ended on a cliffhanger when an adult green dragon crashed through the forest canopy and landed in front of them with clearly hostile intent.

Today, we kicked off with a wisdom save, and most characters were frightened (and rightly so) of the dragon. They tried to talk, and the green monster was clearly amused toying with their attempts to intimidate or persuade it. Once combat began, it dealt a heavy blow to the party's fighter and shrugged off their best attacks. However, they made themselves just difficult enough to kill and hit it with just enough damage that the dragon left for easier prey. A party of 10 level 7 characters can actually make life difficult for a single CR15 monster who has no minions to better divide their attention, and the constraints of a dense forest and narrow path limited the dragon's ability to fight properly.

Once they patched themselves up, their guide led them to a clearing where they were promised a hidden item of power to help thwart the real Big Bad they are destined to face before they can return home. And here is where things got interesting. I decided they could find a Talisman of Pure Good hidden in the ruin behind a rock marked with the glyph of their druid allies. A successful investigation check uncovered the secret cache, and the rogue reached into the chamber to retrieve the item.

I rolled the dice and asked their alignment. Neutral. "You take 23 points of radiant damage."

He tried again. I rolled the dice. 21 more points of damage. He stepped back with a single remaining hit point and invited someone else to give it a go. The fighter who had made himself a one-warforged wall of protection for the party on countless occasions and sought to protect all around it suffered no damage whatsoever for some reason.

At last, the party found the living cathedral at the center of the forest where they hoped to meet the leader of the druids and learn what was really happening. He was absent, but the members present invited the party to stay and rest. But it was time to wrap up, so time for another cliffhanger as a scout rushes in to report treason and the capture of the leader! I need to make cliffhangers a bigger part of my strategy, assuming I can keep the party on track for the schedule to work.

I don't usually put too much weight on alignment, but there are items in the game which use that mechanic to good effect. This talisman is one of them, and I know some of my players are being edgy and playing evil or chaotic characters. So especially in the Feywild where fairy tale laws apply, I plan to mess with their characters in all kinds of ways. What are your favorite "traps" which only harm players for being greedy or petty?