Zup! 8

Zup! 8 is the eighth instalment in Quiet River's long-running series of minimalist physics puzzles, and it sticks to the formula the series built its reputation on. Every level is a small two-dimensional scene with a single goal: keep the blue ball resting on a designated platform for three seconds. The means by which you achieve that are explosions, gravity, falling blocks and the chain reactions that follow from whichever piece you tap first.

The puzzles run lean. There are sixty-plus levels in the campaign, no narrative, no tutorial beyond the first few stages, and no upgrades, lives or currency to manage. Each level is a self-contained physics experiment that asks you to identify the right starting point and let the simulation do the rest. Solutions are usually obvious in hindsight and stubbornly invisible until the moment they aren't.

The series is also famously generous with achievement payouts — Zup! 8 ships with 2,220 of them, alongside trading cards, emoticons and Steam backgrounds — which is part of the appeal for collectors as much as for puzzle players. The engine is Clickteam Fusion 2.5, the underlying design follows from an example by Sergio Andre, and Ann Sharova provides the music. It's small, deliberate, and exactly as long as it needs to be.