New difficulty 30 achievement, bugfixing

The Ouroboros King

The Ouroboros King combines the strategic depth of chess with the build variety and replayability of roguelikes. Assemble a formidable army, discover powerful relics, and buy surprising gadgets to defeat the Coven.

Added the witch hunter achievement after defeating the Coven at 30 difficulty, you should also get it upon loading the game if you beat the game at 30 difficulty in the past. Fixed the consecutive stalemates bug, the softlock bug and some bugs regarding the interaction of marching boots with other items and relics.