Okay, so you all may have heard of Mic Qsenoch's Golf Variant. If not...
Let's come up with some new variants!
1. Warring Warriors
The goal of the game is to be the only player with Warriors left when a Warrior gets trashed. You can buy any cards, but you are not allowed to upgrade into Hero or Champion. And if you have all 5 Warriors in deck, that is another win condition.
2. Knights & Lurkers
The goal of the game is to thin down your deck to only one card. The only cards you are allowed to buy are Knights and Lurkers. This makes Dame Anna really powerful!
I'll post more weird variants when I think of them, and I might try playing some of these later on for fun in a stream or something.