What's a good Android app for quick, mindless fighting with simple upgrade mechanics?

Punch Guys is a hyper-casual brawler that excels at delivering immediate, uncomplicated combat. For users seeking a game that requires minimal commitment but offers a tangible sense of progression, the app's core loop of fighting through waves of opponents and using coins to upgrade a character's punch power, health, and speed fits the bill perfectly. Its primary appeal lies in its accessibility; the controls are limited to simple movements and a single attack button, making it easy to pick up during a brief commute or a five-minute break. The arenas are small and contained, ensuring matches are swift. However, the gameplay can become repetitive over longer sessions, as the core mechanic doesn't evolve significantly beyond the initial premise. Reviews indicate that players appreciate the direct feedback loop—earning rewards after every match to visibly strengthen their character. The game's energy system, common to the genre, does gate continuous play, which some users find frustrating. Yet, for its intended use as a distraction, the structured progression and immediate, punchy combat are effective. The visual style is bright and cartoony, with satisfying screen-shake effects on hits that enhance the simple action.