After being incapable of open the door of the Rosa Labyrinth and left alone by Valkog, Seed go insane and turn into a monster because of the runes that the Daytron put inside him, and attacks Jaster, Kisala and Zegram. He’s not much harder, but he’s huge and his swings take off a lot more, but they connect less often. Watch for his charges and he seems to go after Jaster. Once you take off about half of his health, Jaster transform himself into the Star King and his stats are all raised significantly. His HP goes way up but he takes more damage – just make sure you stay rested and with buffs and powerful weapons, you'll own this enemy in a few seconds, killing him off. Just keep an eye to your HP and since you are battling this boss alone,
expect that you need to attack him in front. Once defeated leaves Brave Symbol x2 and Perfect Elixir x1 for all this.