The game uses a vertically scrolling playfield viewed from above. The player pilots a combat craft through a fixed series of stages, destroying ground targets, aircraft, turrets, and large bosses while avoiding enemy fire.

Pressing A fires the standard shot; holding it changes the attack to a focused lock-on laser. The laser is especially powerful at close range and can lock onto multiple enemies. B uses a limited bomb that clears bullets and damages enemies. Progress is based on survival, stage completion, and score rather than branching exploration.

Ketsui’s scoring system rewards aggressive play and collecting numbered chips dropped by defeated enemies. Maintaining effective attacks at close range and collecting the resulting items increases score potential, while mistakes consume lives and reset momentum.

Learn enemy entrances and boss patterns instead of reacting only after bullets appear. Ketsui’s stages are fixed, so repeated runs can turn dangerous sections into planned routes.

Use the focused laser at close range against durable enemies and bosses, but disengage before overlapping bullet patterns become unsafe. Preserve bombs for situations where movement is blocked or a life is otherwise likely to be lost.

For scoring, stay close enough to generate valuable chips and collect them consistently. For survival, prioritize safe positioning, identify the intended gaps in bullet formations, and avoid chasing every item.