Title text: There's also a Katamari level where everything is just slightly bigger than you, and a Mario level with a star just out of reach.
Tetris is a game where the player has to manipulate falling blocks into forming complete rows. This comic is a play on this, presenting the player with a version of the game with a curved bottom that renders forming rows nearly impossible. Hell is a religious concept of a posthumous punishment for wrongdoers, depicted in many religions as eternal torment.
The title text presents similar situations where frustration is likely to occur. Katamari Damacy is a video game in which the player controls a sticky sphere which grows by assimilating objects smaller than itself. Super Mario is a long-running franchise of platforming games; in most of the games which utilize a 3-dimensional engine, levels are completed by collecting large, golden stars.
Also see comic 888: Heaven, which presents an opposing situation in which the game is trying to help the player win.
There is a playable version of this comic at geekosystem, which, unsurprisingly, is frustratingly difficult to play.
- [A basic Tetris screen is depicted, with a next piece indicator, score and top score, and level listed as 01. The bottom of the pit is curved into a semicircle. A square and L piece are sitting crookedly in the pit; an S piece is falling.]