One of the big classics that many remember fondly but only when reminded is Galaga. I mean Galaxian. Deluxe Galaga?
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Galagian is a spiritual successor to the old classics Galaga and its own descendants. Fight against harder and harder waves of enemies as you get equipped with stronger weapons and avoid the hell of bullets.
With 13 different enemies to fight, 14 gear levels and 43 waves in total you’re probably not going to finish it on your first (or fifth) try.