Warship Gunner 2 - Unlock Special Mission Mode

Unlock Survival Mode:
Clear the game once on any difficulty

Unlock Ultra Hard Difficulty:
Beat game second time.

Unlock Very Hard Difficulty:
Clear the game once on any difficulty

Adjutant Voice Select training only:
Clear the game once on any difficulty

Enemy Layout Select training only:
Clear the game once on any difficulty

Rubber Ducky ASW tech:
Beat the game two times on any difficulty