Seahomon

Seahomon is a Sea Animal Digimon whose name and design are derived from the seahorse. It is an Armor Digivolved form of Armadillomon through the Digi-Egg of Light who dwells in deepest depths of the Net Ocean. Its body is smaller due to the water pressure, but it regains its size near the ground.

Digimon World DS
Seahomon digivolves from Ankylomon if it's holding the Digi-Egg of Light.

Digimon World 3
Seehomon can only be found in Asuka's Central Sector, in the Central Park's seabed towards Bulk Swamp in the South Sector if you have Kumamon at lvl. 45. If you give him Zodiac and Tempest Arm, he will make Prominence.

Digimon World Dawn and Dusk
Seahomon digivolves from Armadillomon with the Digi-Egg of Light when he is at Lv27+ with 2700 or more Dragon EXP

Digimon Fusion
A Seahomon lives in Disc Zone and serves as the spokesperson of its inhabitants until the Zone itself collapses due to Bulbmon's rampage. Thanks to Xros Heart, Seahomon escapes with the other citizens to the Shinobi Zone where they are given nutrition and shelter and find themselves a second, temporary home. Attacks
 * Prism Rainbow
 * Dragon Noise (Dragon Drop)