Released as a promotional partnership between Takara Tomy and the game Phantasy Star Online, this variant of the Wild Liger came in pretty late in the game compared to its brothers. Pretty much around the time the third Liger, Rising Liger was released.
One interesting detail, the stickers are based on the armor of a player character.
Compared to Blue Flame and other more widely distributed sticker sets, PSO has many more stickers covering its body.
While it utilizes the standard Wild Liger box, it has a PSO promotional band around the box to differentiate it from the standard release.
Stickers and Instructions:
The kit also came with a promotional code to download Wild Liger based armor in the game.
PSO related images: