Trizeal

Trizeal is a Japanese vertically scrolling shooter developed by Triangle Service and released as an arcade video game in 2005.

It was ported to the Dreamcast and PlayStation 2.. Players control and can transform a spaceship into three forms (which alternates weapon attacks), working through multiple levels and boss sequences.

A ship from Triangle Service's previous release, XII Stag, is hidden in the game and can be unlocked by holding the "X" button before selecting a stage in Stage Attack mode.

There are six levels in the game, they get progressively harder until the last stage which consists of only two bosses.

Furthermore, it also claimed it would not be a net-only release because it wanted the game be displayed in shops.