rjtstack

Stack fast. Every piece counts.

Guideline rules at 60 Hz with SRS and 180s. Instant clears, finesse judging, exact replays and a CPU to race.

Clear 40 lines as fast as you can. The clock starts at GO after a 3-2-1 countdown; finished runs go on the leaderboard.

Two boards, TETR.IO attacks, configurable bot speed. First to top out loses.

Pick a bot for each side and watch them race on the same pieces. Save the match to watch again.

No timer and no top out. Unlimited hold, and undo takes back a placement.

Zen with CPU-Humanish watching. It stops you after a stacking move that was clearly worse and shows the better spot.

Wells and positions picked at random. Clear a line with every piece.

Server-saved input replays with deterministic playback.

Sprint leaderboard