Panel

Panels are multicolored square shapes that appear in the puzzle game Tetris Attack. They are the main puzzle-solving element of the game. They mainly come in green with a circle, purple with a diamond, red with a heart, yellow with a star, cyan with a triangle, and blue with an upside down triangle.

Tetris Attack
During gameplay, each player has their own playing field where a stack of panels rises from the bottom; if it reaches the top, that player has lost. To prevent that from happening, the player much match three alike panels either horizontally or vertically, which causes that row of panels to disappear from the stack. This is done using a rectangular cursor that can only select and switch two horizontally adjacent panels at a time. Panels are also affected by gravity and will fall in gaps, which allows them to move vertically, but must be in place in order for the alignment to count.

It is also possible to attack opponents through the use of Shock Panels (grey with a white question mark), Chains, or Combos. Shock Panels create Shock Blocks, Combos create short Garbage Blocks, and Chains create long Garbage Blocks, which litter the opponent's playing field. Chains are caused by either aligning four or more panels together or when panels sitting on top of a cleared row fall and are themselves cleared. Combos are caused when four or more panels are cleared simultaneously. The Garbage Blocks caused by these reactions cannot be moved or eliminated, and rest at the top of the stack; however, clearing a row of panels touching the Garbage Block will make it transform into more panels, which in turn will affect other Garbage Blocks of the same color that may be touching it. If the Garbage Black has thicker width due to large reactions, this will require action on each layer separately.