Unstoppable needs to be removed from the Chaos Node.
This is an unfair design that disrupts the flow of combat and punishes the player more than the AI. When this occurs for the AI, the player wastes a Special Attack, as the AI immediately blocks the Special, limiting the damage done, while also being able to immediately attack the player, almost always resulting in a KO against the player.
Years ago, Juggernaut used to randomly go Unstoppable, sometimes even in the middle of combos being received. This was removed because Kabam openly expressed that it was broken for combat. This is a similar situation. This does not revolve around skill, or planning, or adapting, or any other sort of option that the player can counter. It only prevents the player from playing.