Blockfall

Everything that gives the genre a skill ceiling, rather than a well and a number that goes up.

Hold keeps one piece in reserve, swappable once per piece, which turns a bad bag into a decision instead of a sentence. T-spins are detected by the three-corner rule and pay more than the lines they clear otherwise would, which is the only reason anyone builds an overhang they cannot drop into. Combos compound across consecutive clears. Back-to-back pays half again for tetrises and T-spins chained without a plain clear between them.

The gravity is a table, not a formula, because the shape matters more than the elegance: level two is a fifth faster, level four is nearly twice level one, and level nineteen is a kill screen. The well changes colour every level so a level-up is an event rather than a number ticking over.

Underneath: a seven-bag randomiser so you are never starved of a line piece, wall kicks so a rotation against a wall nudges instead of failing, lock delay so a piece landing on a ledge can still be slid, and a ghost. Those stop it being unfair. The rest is what makes it worth getting good at.

Written for this site by PunkyBruiser. If something is broken, say so below.