Here are some secrets not mentioned in the manual, at least not in the US one. Those secrets are not considered as cheat or glitch and they can be use in the speedrun

Destroy gate earlier

Instead of waiting for the game to blink and throw a bomb arrow at it, the game would allow you to destroy it with the M-60 bullets. It works for every level (except level 6), when you are on the end screen (boss)

• Kill at least 16 enemies
• then shoot at the gate many times (~16 times?) with the M-60

150 ammo bonus

There is a 150 arrow bonus when a specific enemy is killed with the 2nd shot of the M-60. For example if you kill the 6th spaw with your second bullet you will get it.

• Round 2 --> 8

• Round 3 --> 6

• Round 4 --> 5

• Round 5 --> 8

• Round 6 --> 7

Super Stinger

this super stinger upgrade will clear all the enemies on the screen when you fire it, except the tanks and motorcycles. All you need to do is to kill 4 enemies on the screen with one M-60 shot, you will need to get the "S" power up to shoot through enemies

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