The craziest thing that I have ever seen (craziest, not dumbest), had to be the adventure which featured the very first Flashhammer characters. Sir Tancred and Sir Indarion of the Ancient and Most Noble House of Flashhammer joined the party – a pair of brash and foolhardy gentlemen ready to take on adventure head-on wherever it may be. The party leader was not the... strongest of characters, and didn’t really lead so much as meander. And so it began.
The party had to invade a fortress built into the side of a mountain, where the wall of the fort literally met the edge of the mountainside. I had provided them with information about less-guarded back entrance through a mine. It had a few enemies and was stuffed with loot, and made a nice and straightforward adventure. The Flashhammers objected to this course of action, as it involved striking an enemy from behind. They suggested instead attacking the fortress head on. When this was decided to be suicidal, they instead thought of climbing up the side of the mountain, and then using Feather Fall to float into the fortress onto unsuspecting enemies. The plan was foolproof, at least, that’s what the knight in full plate thought about climbing up a mountain and then jumping off. The party leader, to the astonishment of all (including the players playing the Flashhammers, who thought it was a ridiculous idea really) agreed.
What followed can only be described as insanity, with the climbers being spotted, falling relatively gracefully onto the wall, and then hacking their way through dozens of bugbears. At the end of the battle, most of the party had only a few hit points left, and the situation had looked pretty grim. When I discovered that I had forgotten a few of the bugbears, I decided that they never existed. They won that battle, but they used the craziest possible plan to achieve it. Parachuting off of a mountain whilst being shot full of arrows is one of the most unique methods of entry to battle I’ve ever seen.
They never found the secret doors in the mine where the treasure was.