Shadowdramon Mega is one of Shimidramon's Mega level, and is Helixmon's alternate digivolution. It can control the shadows, create clones of himself and become shadow like Shadowdramon could, but without cutting its power.
When it become weak, he enters into rampage, raising its power to a level that can match even the stronger digimon. And he can control common machines, like Helixmon.
Its almost exactly as Shadowdramon, but he is about 5 times his size and he have legs. Shadowdramon Mega can copy the enemy's form, equalling their speed, size and weight.
He can also possess the soul of any Nightmare Soldier that touches.
Supreme Shadow Serpent: Transforms itself into dark matter and attacks the enemies, eating their soul to raise its own powers.
Rage of Darkness: Unknown attack that weaken light power and strenghten dark power.
Mega Shadowblast: A blast with the power of all the shadows in the digimon world, destroys completely any digimon!
Alpha Creator: Re-creates any digimon destroyed by the "Mega Shadowblast", into a more powerful one under the control of Shadowdramon Mega.