It's basically me Biomerged with my little Betamon- not GigaSeadramon because that's his regular Mega form.

Plus, I think I figured out how the whole Biomerge dealie works. Well, you see, when the Tamer's data is "stripped down" so to speak, it is being matched with the partner Digimon's Digi-core. Hence the glow color- Guilmon has an orange core, Renamon has blue and Terriermon has green.
The Tamer data merges with the core data upon matching and forms an "upgraded" core, thus forming an "upgraded" Digimon.

What? Betamon's core color?? It's a kind of greenish cyan.
...And MegaGargomon is awesome.