Here is the full list of all 126 COMBAT INSTINCT achievements.
Unlock Koga
Unlock Likoga
Unlock Lava Cutter
Unlock Lightning Lava Cutter
Unlock Orbital Cannon
Unlock Smashing Energy Cannon
Unlock Split Bolts
Unlock Smashing Split Bolts
Unlock Dark Stir
Unlock Energy Cannon
Unlock Haze Blast
Unlock Shoryu Blast
Unlock Ryuga
Unlock Superalloy Grapnel
Unlock Jet Dash
Unlock Rifled Cannon
Unlock Ultra Orbital Cannon