Video game boss battle where enemy ignores you. Easier or Harder?

In most video games, in boss battles, your enemy always engage you when you fight them, they usually fight with equal strength, if not more. But what if there were a boss fight where the enemy completely ignores your presence and/or they try to avoid you at all costs so they absolutely want nothing to do with you.

I had an idea, an antagonist who has a cold distant personality so he naturally believes its ok to ignore people, he’s also very focused on a particular hobby, so when you try to fight him, he’ll never stop what hes doing. You actually try to fight him many times through the game, but the main character cant emotionally bring himself to even bother with him because there’s nothing he hates more than being ignored! and the character also has the power to make everything he ignores disappear, so nothing else except what he focuses on matters. That means all damage too, if hes harmed, the damage disappears if he ignores it(like a way to “cure” himself), and theres also a chance YOU could disappear if you’re within his radius after a certain amount of time, so you’d need to find out an action that will prevent him from ignoring you, to defeat him. and that happens very close to the end of the game. You cant finish the game unless you defeat him.

In your opinion, would that make the fight Easier, or Harder?