Grimmon

Grimmon is a Digimon whose name and design are derived from the Grim Reaper.

Digimon World Dawn/Dusk
Grimmon first appears as a hooded figure in the Thriller Ruins, spotted by Night Crow as they investigate an outbreak of violence in local Digimon. The figure later appears after the Normal Tamer Tournament and is chased back to CITY, where it is revealed as an egg-shaped purple "Mystic Energy" who attacks CITY and uses its "Chrono DSR" to degenerate all of the Digimon to Digi-Eggs, except for the player's Digimon and NavDigimon, the Team Leader, Bokomon and Neemon (who even comments how odd it is that they didn't degenerate), and in Dawn, a Gigimon, or in Dusk, a Kapurimon (who both wonder if it's because they aren't Digimon). The protagonist defeats the Mystic Energy inside of their respective headquarters, which then flees. The "Mystic Energy" is encountered again in Limit Valley, where it displays the power to control Digimon (Seasarmon and SandYanmamon in particular), which it uses to attack the protagonist before finally revealing itself as Grimmon.

After being defeated once more, Grimmon shows up at Access Glacier, where it has the protagonist's Chief, the Chief's partner, and his/her friends under its control (Chief Glare and Ophanimon in Dawn and Chief Julia and ChaosGallantmon in Dusk), using its ChronoDSR ability. When the technique fails to work on the protagonist, it sends the Chief's partner at him/her before fleeing.

It appears once last time in Chaos Brain, where the Chrono Core fuses with it to become ChaosGrimmon.

Attacks
 * Chrono DSR (Chrono Destruction): Degrades and destroys any data in the Digital World.
 * As Mystic Energy
 * Call Cat: Summons a cat to attack one zone, lowering resistance to Light.
 * Call Bat: Summons bats to bite one zone, inflicting Poison.
 * As Grimmon
 * Call Bird: Summons birds to cut two zones.
 * Call Dragonfly (Call Yanma): Summons dragonflies to drop lightning on two zones, inflicting Paralyze.

Attacks in Digimon World Dawn/Dusk
 * As Mystic Energy
 * Dark Crusher: Destroy data in one zone with an arrow of darkness, inflicting Paralyze.
 * Small Breath (Petit Flame): Unleash a small fireball on one zone.
 * As Grimmon
 * Power Cutter: Slashes two zones with powerful quick crisscross attacks.
 * Black Blast: Attacks one zone with an energy ball of darkness, lowering resistance to Dark.
 * AT Change: Changes own strengths and weaknesses.