Welcome to King of Stackers, a turn-based strategy game in which you must stack blocks in neat rows. Doing so fills your opponent's field with random blocks, making it harder for them to arrange their blocks. Twisting blocks into tight spaces, or stacking a lot of rows at once, will put your opponent in greater jeopardy.

A comprehensive (but now slightly-out-of-date) description of the game and basic strategies can be found here. Please refer to the Changelog for the most up-to-date information.

Some notes for players:

• 180° rotation does not quite work how you might expect it to - namely, it is very inflexible, and has almost no kicks.
• Spins are tested for using Immobile detection, not 4-point. As a side-effect of this, EZ-spins are not rewarded.
• Spins where the locked piece both kicked and does not clear all lines it is dropped into are considered mini. Mini is a -1 to attack.
• The combo table looks like: 0, 1, 1, 2, 2, 3, 3, 4, 4, 4, 4, and so on, capping at 4.
• Clearing lines with a spin, or getting a quadruple, will give you a Back-to-Back bonus. If your next line clear is a spin or a quadruple, this will give you +1 to its attack.

Thanks are due to the members of Hard Drop for their support, and to Blink for giving us the nifty shortcut URL http://www.harddrop.com/kos.