Reaction Rudder: Metal Work + Special Rudder
Evade Collision Attack: Control Tower + Special Rudder
Direct Hit Prevention: Control Tower + Mast Top
Command Post: Control Tower + Admiral's Cabin
Diversion Cannon Fire: Control Tower + Special Gunpowder
Welcome Melee Battle: Stern Deck + Admiral's Cabin
Drainage Pump: Special Ship Hold + Set of Repair Tools
Improved Gun Port: Admiral's Cabin + Munitions Chambers