Your ship has: health(red bar), ion(blue bar) and energy(green bar). You lose health when you get damaged. Ion is spent when using ion powers: E.M.P. Nova and Cryo Grenades. You can replenish them with health kits and ion kits. You use energy to shoot, evade and block.

You earn credits(bottom right corner) as you destroy enemy fighters. Spend them on upgrading your ship by returning to the Base Ship (enter by approaching the runway). Every minute a base ship is spawned. You can either enter it to upgrade your ship or proceed to the boss battle!

There are 4 enemy types:

The Brown Agile Fighters - evade your attacks and shoot back at you!
The Pink Kamikaze - small suicide ships.
The Yellow Rail Ships - fly in formation and have a fixed pattern of attack.
The Green Tanks - large but slow bullet sponges that fire heavy bullets.

When your ship is destroyed, you lose all your credits, but keep your upgrades! So, spend your credits whenever possible! You have unlimited respawns.

Controls:

ButtonsActionW, A, S, DMovementLeft ClickShootShift + Left Click (Hold)Charged ShotEUse Ion Power (blue bar):
E.M.P. Nova/ Cryo GrenadeRUse Replenishment Kit (slows down movement):
Health Kit(red bar)/ Ion Kit(blue bar)
SpaceEvade (consumes Energy)FShield
- Holding up the Shield stops Energy Regen
- When projectiles hit the Shield (Energy is drained instead of Health)"Up" Arrow KeyCycle:
E.M.P. Nova/ Cryo Grenade"Right" Arrow KeyCycle:
Machine Gun/ Shotgun"Down" Arrow KeyCycle:
Health Kit(red bar)/ Ion Kit(blue bar)

ShootEmUp - with DarkSouls Elements screenshots