why do I have to fight a donut and an octahedron

What game is that

the game is called Slay the Spire and you can buy it on Steam, it's not very expensive like some other games

Hey guys welcome to donut gaming

hey guys so today we're going to be committing geometricide.

The lore is The donut destroyed worlds and the octahedron is nikacado avocado's little brother