Dumbest thing a PC ever did!
On X1 the Isle of Dread, one of the PCs (a female dwarf thief named badger) insisted on us following a megatherium (giant sloth), because she wanted to make it be her mount. We refused, and continued towards where we were supposed to go.
Badger then abandons the party, and goes on a looooooooooooooooooooong solo adventure. (The GM btw should have been flogged for running that person's solo for hours while 5 of us were sitting there waiting to play). During that solo, she finds the megatherium, and it totally ignores her. It is so big that it is pulling trees out of the ground to eat, so she does not try and attack it.
On the way back to the group (we were walking several hours in the opposite direction) she was bushwacked by trolls, and only managed to outrun them because of lowhanging tree branches.
Later, she walked right into a camp of 4 areaneas and began getting blasted by magic missiles, etc. She ran for her life. (even though she was a theif, she had a 19 CON and the most HP in the party)
Then, she ran into a T-Rex, who chased her up a tree, which was overlooking a cliff. After shaking the tree she decides to jump down the cliff rather than be eaten by the dinosaur. She is now hovering on death's door at this point with only 2 or 3 HP.
She decides to find a safe place to rest, to regain HP overnight.
During the night, she has an encounter with a wyvern. Although it attacked her in her sleep, and the other 5 players begged the GM to just rule it automatically hit, (which would likely have killed her), he was nice and rolled. He hit AC 15 by 3rd Edition reckoning, and said okay, you were hit for 4 damage, make a save vs. poison. The player then jumped up and claimed, NO! MY AC IS 18, because I am wearing +1 Chainmail! The GM retorted that if she was resting to regain HP, she was not wearing armor. TO which the player replied, fine then, I don't want the HP, for survival I decided I needed to sleep in armor. So the GM allowed him to totally reverse the stated action of the character for that night, and the attack missed.
She then hit the Wyvern for critical damage, and killed it. A miracle she survived-- but this is not over!
The next morning, worn out, and unhealed (she did not regain any hp because she slept in armor) she sees a green dragon drinking water at the lake she was going to drink from. Rather than try to hide from it (which would have almost been a guaranteed success with her elven cloak and boots) she walks up to it and says hello!
The dragon sees her, and starts laughing, then says she can live if she gives him all her magic items! (the other players began really rejoicing over this, because she had been taking more than her share of items from teh begining)
She does it, and the dragon lets her go.
Eventually she reunites with the party. She says that a dragon attacked her and took all her stuff. We agreed to help her get it back, but she did not get a share of the spoils other than her own stuff back. That was the worst mistake we ever made because this dragon's entire horde was made of her items! So we did not get anything for helping her-- not even a finder's fee!
After many more adventures where badger was the proverbial thorn in our sides, doing too many sidequests by herself, trying to force the party to do what she wanted, etc, she finally died!
After seperating from the party yet again, she was in an area where she had a random encounter with 4 cockatrices. Even though she was bitten several times, she never failed her save! We cursed at each successful save! Later, we got our sweet sweet, moment, however:
She encountered a pair of hobgoblins, who challenged her to a wrestling match! Being overconfident, she accepted. Unfortunatly, her opponents were not actually hobgoblins-- they were Thouls-- Regenerating, Hobgoblins that have ghoulish paralysis! When she wrestled with them, she had to make saving throws every round. She eventually failed, was paralyzed and eaten!
What was better, was that later the party finished a module called "Wrath of the Immortals" in which at the end, the Gods ask you if there are any questions you want answered. We asked to know what happened to badger (she never returned after seperating with us). They showed us a "movie" of it. Although the characters have had multiple opportunities to do so, we have never once used a "wish" to bring her back to life-- even though we did to bring back an ogre hireling of another PC! That really pissed off the player of badger who was now playing a paladin & did not like being "good". Eventually the player left the campaign, and things have never been better!