Utopia Must Fall is a retro-flavored base-defending arcade shooter with rapid progression, randomly generated attack patterns and enough build variety to qualify for the incredibly-overused "roguelite" keyword.
Easy to learn: firing happens automatically, just aim your city's turret with the mouse, and click for the occasional screen-clearing nuclear warhead.
Sizable upgrade tree: progress is fast and allows you to pick build strategies that suit your playing style... beef up your main laser into a triple-spread machine gun of death, focus on your shield's recharging ability and auto-defense, or go all out on nuclear research and control a parade of guided mini-nukes to spray death all over those awful alien beasties.
Laser-shiny: built with the new V99 engine for a retro-modern authentically-fake vectrex style, that you didn't know you needed yet.
Affordable: reasonably priced to help offset the unreasonable cost of everything else.