My former DM had quite a hardon for level 25 characters in 3.5. Sometimes for character battles, sometimes for campaign ideas that he would scrap in short order(usually before the first session).
Knowing he also had it in his that it was his duty as DM to kill the party, I set out to make something gamebreaking without being too obvious about it. So right off the bat, no Wizard and no Druid. He had a penchant for underestimating Clerics, so I used that. The original plan was to use Chuck, the Ruby Knight Vindicator, but I thought to myself:
>Well hold up, what other neat things can we do with swift actions?
So I started flipping through PDFs. Thankfully I didn't have to go far, Complete Champion was up at the top.
You know, Ordained Champion is a pretty neat class, especially the part about being able to spontaneously cast War Domain spells at reduced speeds. Flame Strike takes only a swift action. Ruby Knight Vindicator can generate swift actions like no tomorrow. This became my Emergency Button. I put Trogdor the Burninator into an anagram generator and there was his name.
You have no idea how many times I wanted to push that Emergency Button. He was always flaunting his cool character ideas, doing this and that and whatnot, going on and on and on. Each time I resisted, not wanting to show my best cards, not wanting to forever be That Guy who could take characters that could just unravel his campaigns and fly them under his radar. Of course, I made do with all the other absurdly good Cleric spells, but Emergency Button was that one itch I never got to scratch. Maybe it was for the best.