Walla

Walla (ウォーラ) is a walrus virus from Mega Man Battle Network 4. It is a stationary virus that launches two indestructable fangs when the target enters its row. The fangs are launched on the same row and the row above. If it's on the top row, the fangs are launched on the same row and the row below. The fangs also block projectiles.

Walla
Walla is a brown variant with blue and white clothing.

WallaEX
WallaEX is a light blue variant with blue and green clothing.

Walland
Walland is a yellow variant with green and cream clothing.

WallandEX
WallandEX is a purple variant with orange and yellow clothing.

Waldon
Waldon is a red variant with light blue and white clothing.

WaldonEX
WaldonEX is a black variant with black and red clothing.

Battle Chips
Twin Fang (ツインファング) is the Battle Chip from Walla family.

Anime
A massive Walla appears in the real world in episode 28 of Rockman.EXE Stream alongside several other viruses in Dinosaur Land, a newly opened theme park. It was formed by VideoMan.EXE and Viddy Narcy as part of a plan to materialize thousands of viruses into the real world to create chaos.