We choose as a final boss the villain more iconic in the movie: Grewishka. We choose him instead of another enemy from the manga because he's very recognizable and he's so big, perfect to be a final boss. For design him, we took as a reference "The butcher" from Diablo 3. We were looking to reproduce the in-out combat of that boss.

The boss has two different phases. In the first phase he only attacks with melee hits. When he changes of phase use his throwing fingers to attack Alita. This was done because of make easier to the player to distinguish both phases and to make the combat against Grewishka deeper.

The AI of Grewishka is very simple. He launches one of his three attacks every 6 seconds. He has 3 attacks:

-  The first one is a hit on the floor that makes damage in an area in front     of him. In the second phase, Grewishka also digs with his fingers which     attacks alita rising from the floor. Grewishka use this attack

-  The second is a hand-hit that throws Alita away from him. This is used     when Alita is at a medium distance. Grewishka have very large arms,     so if Alita is away for him he will use this attack

-  The last attack it's only used in the second phase. Grewishka throws his     fingers to Alita and if he catches her, Alita is attracted to him. This attack     replace the Hand hit in first phase for the second one. It's also used     when Alita is away from Grewishka.

With this Grewishka react to the player decision making and his situation what allows the player to have more strategical combat. Testing this we perceived that Grewishka became so predictable because depending on your position will throw one attack or another. To solve this we implement a repetition cap, so if he does two times the same attack, the third will be the other attack, independently of Alita position.