[BOSS] Hammerhead shark

Hammerhead Shark Enemy:

• The final boss enemy
• It is sized at 32 pixels x 32 pixels, twice the size of the normal enemies
• It has 3 attack states

Attack modes:

1. In default mode, it will move and chase the player while firing projectiles occasionally.
2. When its health is low, it goes to a berserk mode. It will interchange between ramming and shooting a barrage of projectiles.
3. In ram mode, it will charge in the direction of the player for a short distance and will repeat this for a certain amount of time. It is invulnerable when it is in this mode.
4. In barrage projectile mode, it stays in 1 position and shoot out projectiles in all 4 directions.

Default mode:

• Follows player slowly
• After a short period of time shoots a 4x4 tile size (16 pixels x 16 pixels) projectile in the direction it is facing

Ram mode

• Occurs when shark health is low
• Will charge up for a short period of time before running in the last direction it was facing
• It will charge a distance slightly beyond where the player was last at.
• It will repeat this behavior a certain amount of times. Afterwards, it will go to projectile barrage mode.
• It is invulnerable during this period of time.

Projectile barrage mode:

• It will stay in one position, and shoot a barrage of projectiles in all 4 directions, for a few times. It is invulnerable during this period of time.
• Afterwards it will 'rest' for a while, in which it will be vulnerable to player's projectiles.
• Then it'll go back to Ram mode