Here is a technical demo of my open-source game. It lacks a menu and any settings, and the graphics are highly sketchy. My main goal was to test the idea of the gameplay.

Summary:

The game field is represented by the player ship, targets, and black and white holes. The player can control the position of his ship and produce the energy pulses. The targets and black and white holes appear at a random location and have a limited lifetime. The black and white holes have gravitational effects on the energy pulses of the player (but not on the player ship). The game goal is to hit as many of the targets as possible with the energy pulses.

See details on its page: https://thewizardplusplus.itch.io/gravity-duel