Asgardian Spartaxians War

According to Rocket Raccoon this is the biggest war in galactic history.

Arrest of the Guardians of the Galaxy
PETER: You're an funny dude, Dad. I just about died laughing when I heard you want me to help you steal the Cosmic Seed for the second time. I will not have this outrageous slander in these chambers, Peter. Guards! (THOR GRUNTING) This is an unmitigated act of war with Asgard! There will only be peace when we have wiped Spartax from the face of the galaxy!

Battles
Peter Quill(Star-Lord) vs. King J’son of Spartax

Episodes
Asgard War Part One: Lightnin' Strikes