You can unlock more credits to play with simply by playing the game for certain periods of time. For instance, playing for sixty minutes will get you five additional credits, while getting your total playtime up to five hours will unlock an unlimited amount of credits for you to use.
"R.A.D" Master (25) Complete Single Player Arcade Mode without continues using R.A.D.
30 Second Max. Bonus (15) Maintain the max. bonus for 30 seconds or more.
Cleared Stage 1 (10) Clear Stage 1 in Single Player Arcade Mode.
Cleared Stage 2 (10) Clear Stage 2 in Single Player Arcade Mode.
Cleared Stage 3 (10) Clear Stage 3 in Single Player Arcade Mode.
Cleared Stage 4 (10) Clear Stage 4 in Single Player Arcade Mode.
Don't Let Me Go (15) Hold onto an enemy for 10 seconds or longer with the anchor using Ruby.
Incredible Restraint (15) Go 30 seconds without swinging Sensei's sword.
Ruby Master (25) Complete Single Player Arcade Mode without continues using Ruby.
Sensei Master (25) Complete Single Player Arcade Mode without continues using Sensei.
Tempest Master (25) Complete Single Player Arcade Mode without continues using Tempest.
Untouchable (15) Repel 20 or more enemy bullets using Tempest.
