There have been loads of updates and bug fixes in the past week or two! First thing to note is that the Steam Overlay is working :D
Beyond that, there have been dozens of fixes to Interstellar Invaders!

• Two-player CoOp mode is available from the start of the game
• You can now access CoOp mode from the menu screen mid game
• The first boss has been updated to have additional obsticles in CoOp mode
• Colors work properly while in Inverted mode
• Other bug fixes that I can't remember!

[ 2018-04-14 20:47:44 CET ] [ Original post ]

Interstellar Invaders is an arcade game which combines the game mechanics of Arkanoid, Galaga, and Missile Command in hand-built and procedurally generated levels.

You defend three cities against enemies, with intuitive and surprisingly deep design mechanics. If all three cities are destroyed, the level is lost.

The foundation of the game is based around the mechanics of Arkanoid (and/or other Brickbreaker style games) – but with a number of important improvements. The paddle is aligned to the mouse position at 60 frames per second (on most machines) which gives maximum player control. Players also have the option to use the mouse buttons to direct the ball for additional control while it flies. No longer do you need to wait for physics to slowly inch the ball in the right direction – you can hunt down the bad guys!

There is an entire armada of enemies – each with different attributes and attacks. Enemy’s fire can be blocked by your ship’s shield and turned into a projectile to destroy the invader from which it came! There are also a number of unique power-ups and power-downs in Interstellar Tortoise that often stack up in unexpected ways.

The core of Interstellar Invaders is the ‘Hordes Rush’ mode, which is unlocked after beating the first 32 levels. In this mode, each level is dynamically generated – the mix of enemies, their flight patterns and the environmental hazards are all randomized, so each play-through will be a different experience.