Wow this game is extremely difficult, especially the fourth phase. I will beat it eventually though. My rating is 10/10
Update: Made it to the boss battle, oh my god the king is stupid strong
I finally beat it! Here's my strategy:
Back row: Stonetosser (Excalibur in the middle, use big buff on him)
2nd back row: Rats
2nd front row: Summoners
Front row: Succubus
Extra row: Mausoleum (sell it right before boss battle for additional 3 coins), summon spell,use the empty slot if needed
