You'll find boss Geo Hypostasis in the Guyun Stone Forest area in Liyue, and just like the other two bosses, he'll present his own challenge when you fight him. The good news is that with a few simple tactics, this is actually the easiest of the Hypostasis boss fights.
First of all, you will need to organize a party. Bring the healer of your choice, an Electro character and a Pyro character. Razor will really excel in this fight if you have it. Any Claymore character will be great at breaking through pillars and preparing for an easy victory through simple strategy.
The Geo Hypostasis will create pillars in the arena and then sit on them safely. If you can't destroy them quickly, it's better to break them to around 90%, then wait for the geo-hypostasis to come back to them, don't waste your efforts breaking them after the boss has already moved the pillar, just leave for an easy smash the next time they go back.
When you break a pillar that the boss is on, it will fall to the ground and you can start hitting it. The Cryo and Electro stack will tear it apart in no time. What you will need to watch out for are the multiple attacks it can launch, some of them are very dangerous.
The boss will throw stones at you and hit you with a shock wave attack that can knock you back. It will also drop rocks from the sky on you, but these will be telegraphed by circles on the ground. The main thing to watch out for is when multiple shock waves are coming from all of the pillars, dealing damage. It's best to run if the pillar is healthy, as it will do massive damage and can kill you.
When you lose enough health from the boss, it will form three pillars in the center of the arena that you need to kill. Each pillar will be reabsorbed into the boss, healing them for about a sixth of their health. You must destroy them all within 15 seconds. If not, just repeat the steps until he's completely dead and you've destroyed all the pillars.
