It was like galaga/space invaders -- you shot oncoming swarms. Only it was bugs (like galaga), yet you could "capture" lots of bugs -- have something like 8 bugs on either side of your ship, and on some bonus levels, you'd "bounce" the oncoming ones -- kept shooting them, and they'd bounce back up, and more points etc.
No luck ever remembering what it was. Played it at sports camp many, many years ago.. MAME didn't help me, nor wiki.
And I tried googling it, but too many of the sites are blocked here (even google pictures) so I couldn't make a call on it..
But your comment about bonus rounds bouncing the bugs sounds spot on... I just remember "juggling" the bugs got more points -- the bonus was for how many bugs you hit, and each time you hit one and it recoiled back up, you could keep shooting it for a long time, racking up the points.. [ Parent ]
Gaplus was a the third in the Galaxian series (after Galaxian and Galaga). It also didn't hold you on the bottom of the screen but allowed you to move... [starts up MAME, starts Gaplus, waits, tests] a full halfway up the screen which could be useful but also very dangerous.[ Parent ]
(I'm afraid I lost those ROMs, though I leeched many from classicgaming.com back when they actually linked to roms for emulators like MAME and nesticle, SNES emus etc)[ Parent ]