Can you ever rebattle Mewtwo in Pokemon HeartGold ever again if you killed him?

Question

I accidentally killed him because of stupid Burn!

Answer 1

Yes, simply just beat the Pokemon league again.
Source

Comments

i cant find mewtwo in cerulean cave? do i need to finish something first before mewtwo appears there?

---

no he should be at the bottom of the cave in the room with the rock maze