Mysteryegg is a new Pokemon that exists in Snakewood. It evolves into Secretegg starting at level 30, which evolves into Hyperegg starting at level 43. It is a Normal/Bug type with the ability Shell Armor.
Get from Professor Birch on Route 103.
Level Up Moves
HMs and TMs
Water Pulse, Calm Mind, Toxic, Bulk Up, Grasswhistle, Hidden Power, Ice Beam, Light Screen, Protect, Frustration, Solarbeam, Thunderbolt, Earthquake, Return, Psychic, Reflect, Fire Pump, Facade, Secret Power, Rest, Skill Swap.
Strength, Flash and Dive.
Mysteryegg eventually evolves into powerful pokemon, but prior to evolution it is very weak.