Primal Dialga is a pokemon that appears in Pokemon Mystery Dungeon: Explorers of Time and Explorers of Darkness and Pokemon Mystery Dungeon: Explorers of Sky. He is located in the Temporal Tower and is the final boss of the game's main story line. Primal Dialga is actually just a regular Dialga that lost control over it's ability to control time due to the Temporal Tower collapsing and changed to this form.
Primal Dialga's state is due to Darkrai stealing the time gears this outraged the Dialga and disrupted the proper flow of time. Due to this in an alternate future the Temporal Tower collapsed sending Dialga into a primal rage (hence his name: Primal Dialga.) Primal Dialga is later saved by a being implied to be Arceus
- Although Dialgas are usually referred to as genderless Primal Dialga is stated to be male
- This is the second altered pokemon to have the word dark in front of it's name in Japan (he's called Dark Dialga there) the first being Shadow Lugia (Dark Lugia in Japan)