Four parts! Like "Change your mind"!
1 - Steven fights the Gems and Alexandrite. The Temple gets destroyed (the house was already totalled at the end of last episode).
2 - Steven fights Alexandrite and Perfect Malachite who is the result of Jasper and Lapis fusing to save Steven. Little Homeworld gets burned to the ground.
3 - Steven fights Spectrolite (Perfect Malachite + Bismuth) and the Diamonds. Beach City - fortunately evacuated by Peridot - gets destroyed.
4 - Steven fights Paragon Diamond and Cluster, who emerges up to her waist this time. Her head is in the clouds. For the first time it looks like he's gonna lose, but then huge glowing cracks start to appear in the Earth's crust as waves of energy radiate from the screaming pink beast. White Diamond whispers in horror "It's happening again"... but then Connie - who has been jumping around on Lion to try to get through to Steven - gets hit by debris. She lies motionless, her face bloodied.
That finally quiets him down as the giant monster has a "What have I done" BSOD.
Anyway, Connie loses an eye (Like Pink Pearl! Right? And like that one time in Rose's room! Remember? Foreshadowing used to be a thing) but he heals it unintentionally as he cries while shrinking. She does have a pink eye now though.
And he leaves not just because he wants to, but also because nobody looks at him the same way anymore.
Maybe he shouldn't just leave Beach City, but the planet. Not forever... just a few years. The safety of his childhood has been annihilated. Beach City is being rebuilt as a human/gem town. And Steven flies out to the stars with the Off-Colors... because he realizes he is one.
Growing up should cost you.