[4] A Nintendo Entertainment System sequel was developed but never released, but a playable finished ROM has surfaced online since its cancellation.

Similar to Xevious, the game does not have distinct levels; the background alternates between the surface of a planet and a space field.

[5] In Play Meter magazine, Roger C. Sharpe gave it a generally favorable review and rated it three hashes.

[6] A follow-up game, Titan Warriors, originally known as Neo Vulgus, was in development for the Nintendo Entertainment System, but went unreleased.

The Pow icon is re-used in many other Capcom games, like 1941: Counter Attack, Bionic Commando and Savage Bees.