Age of the Beast was to be the successor of Beats of Rage, the first game by Senile Team. It was announced by Senile Team on April 12, 2004. Like their first game, Senile Team was inspired by classic scrolling fighting games such as the Streets of Rage series.
The game has not been officially canceled. However, Senile Team has stated that, because it was announced prematurely and grew too large to be manageable, "Age of the Beast had to clear the field in favour of other projects".
Unlike their previous game Beats of Rage, Age of the Beast was said to feature original graphics and sound, plus an improved game engine.
On June 3, 2006, The GOAT Store revealed that the game would be available in two versions. The main version was to be a downloadable freeware version. The game would also be available in a commercial special edition for the Sega Dreamcast video game console.
According to the press conference held by Dan Loosen of The GOAT Store at the Midwest Gaming Classic on June 3, 2006, the engine was to be customizable similar to the engine in Beats of Rage, except that it would feature more moves, the ability to ride animals, up to 4 simultaneous players, and a customizable palette for each character. The freeware release would include the full engine, but the freeware game included with the engine wouldn't use as many features as the commercial release. The commercial release would have more features, characters, and unlockable features.
The Dreamcast version was listed as one of the "upcoming [Dreamcast] projects [to look] forward to" in the eighth issue of the British print magazine, Retro Gamer.