新・ロロナのアトリエ マキナ領域・変異ボス：デーモンロード Shin Rorona no Atelier – Makina Domain Distortion Boss: Demon Lord

This one is annoying, and if you have low HP – you’re dead meat. He is lowering your stats, he’s lowering your everything, and he hits hard.
But…auto-use Elixirs, some Mugen Meteor and Meruru’s awesome skill that throws enemy back in turn order beat him easily. MERURU IS L-O-V-E! YEAH!