The evolved version of Nemus. Has two discs that it launches with its spear. Has an extra coat of armor to protect itself from fire, wind, and water. Its crown holds four yellow stones that can destroy the most deadly enemies.
Mega Nemus first appears in Invasion of the Vestals battling Viper Helios alongside with Blade Tigrerra. Baron overdid his defense abilities and Spectra Phantom used Burst Core to nullify and make all of Tigrerra's powers useless. Just as Nemus was about to get shot by Helios's General Quasar, Blade Tigrerra pushed him out of the way causing Baron to lose and her to get captured.
In his next brawl in Get Psyched, Baron acted cowardly and started losing to Shadow Prove. In the end, Nemus talked some courage into Baron and overpowered his fear and managed to free three Bakugan from the Vexos.
In Beta City Blues, Nemus then tagged along Dan and Neo Dragonoid to defeat Shadow Prove's Hades and Mylene Farrow's Aquos Elico and managed to destroy the Beta City Dimension Controller. Mega Nemus faced Mega Brontes in a match to distract Volt.
In Ultimate Bakugan, Mega Nemus saved Baron from falling from the sky palace in ball form.
In Six Degrees of Destruction, Mega Nemus evolves due to the Six Ancient Soldiers giving Drago and the other Resistance Bakugan their attribute energies. Mega Nemus receives Lars Lion's Attribute Energy and evolves into Saint Nemus.
- Ability Cards
- Pyra Might - Skid Roa: Adds 200 Gs to Mega Nemus.
- Raven Lore: Transfers 100 Gs from the opponent to Mega Nemus.
- Shade Cocoon: Prevents the opponent from activating any abilities.
- Spark Roa: Transfers 300 Gs from the opponent to Mega Nemus.
- Corona Hole: Subtracts 300 Gs from the opponent.
- Bolting Arrow: Halves the opponent's power level.
- Shade Ring: Reflects the opponent's ability.
- Ancient Glow: Transfers 200 Gs from the opponent to Mega Nemus.
- Fusion Ability Cards
- Flow Skylight: Switches G-Power with the opponent's Bakugan. (Requires Shade Cocoon to be active and the power level difference must be at least 500 Gs).
In Japan, the Subterra version in BST-12 comes with 500 Gs or 540 Gs. The Haos version in BO-03 and BST-03 comes with 400 Gs, 420 Gs, or 440 Gs. The Pyrus version has 520 Gs and the BakuFrost, Ventus, version has 570 Gs.
- Defenders of the Core Ability Cards
- Orion's Belt: Mega Nemus fires devastating beams in 3 directions.
- Sun Shield: Triggers a powerful combo attack.
- Prism Barrier: Generates a shield to deflect shots.
- Flood of Light: Mega Nemus shoots light arrows into the air that rain down on opponents.
- In the game, Mega Nemus' arms are on the rings on his back, while in the anime they aren't. The same applies to Mega Brontes.
- He and Mega Brontes seem to follow the same evolution line.
- He highly resembles Mega Brontes in ball form.