ClickTap to fire. Hold space to enter transfer mode while stationary.
Pdroid is a partial recreation of the classic Commodore 64 game, Paradroid, originally created by Andrew Braybrook who also made a version for the Amiga. This Flash rendition was started in Flash 5 and completed in 6 using Flasm for collision detection optimization.
Pdroid is old enough to attempt emulating it with Ruffle. Your experience may vary.