Description:

Twin black holes have erupted just outside your space station!  Try to avoid them for as long as possible!  Collect Moon Rocks when gravity is up, and Rocket Fuel Canisters when gravity is down!  Shoot the Switches to switch the Blast Doors!  Avoid Alien attacks!
 

Use A/D or arrow keys to move and space or mouse to shoot.

Dev Notes:

The theme of this Experimental Game was "Weight", so the obvious idea was to center around a gravity mechanic.  The alpha version only had a single black hole and wasn't exciting enough for the professor's tastes, and the beta had two black holes that were constantly open, requiring the player to try and stay in the center of the screen at all times.  I personally was not a fan of that idea, so I came up with the door-switching mechanic to give the player more to do and to introduce more opportunities for different playstyles.

The player has a constant "mass" number, which is increased or decreased based on the collectibles they pick up.  Gravity too is always increasing as the game goes on, and the objective is to keep the player's mass greater than the influence of gravity.  The challenge is that the direction of gravity can change, and therefore the collectibles must change whether their effects are positive or negative based on the current direction.  This was easy enough to check in the code, but was difficult to communicate to the player.  This problem was addressed by adding the positively and negatively color-coded score pop-ups.

But we found through playtesting that these numbers mattered to players very little.  The switching was hard enough to understand, let alone having to keep track of a numerical readout on the side of the screen displaying our arbitrary values.  Our professor suggested hiding the actual numbers and just displaying a gauge of player mass relative to gravity, complete with flashing to show whenever the player is in danger.  This visual solution made the game that much more readable to players.

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