So to defeat the gamma king titan you need 4 mutated dreadnoughtuses on aggressive , an alpha tier forest titan and ice titan set on aggressive, and a mutated carcha on passive for you to ride. (Not gigas cause rage mode is possible) If the king titan starts doing an attack where it charges up its fist with corrupt energy, run away and let your titans and dreadnoughtuses handle it until the attack is done. If your stuff does enough damage while it’s charging up the attack the attack will be cancelled. If your stuff doesnt do enough damage and it does the attack while you are not far enough with your carcha, you get dismounted, you get 1 shot, and your carcha almost gets 1 shot. If you do everything correct you should be able to kill it. Stuff that is not necessary but could help: titanosaur, desert titan, carcha army, and extra dreadnoughtuses. I hope this helps.