Walla (ウォーラ,Walla) 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 is a brown variant with blue and white clothing.
WallaEX is a light blue variant with blue and green clothing.
Walland is a yellow variant with green and cream clothing.
WallandEX is a purple variant with orange and yellow clothing.
Waldon is a red variant with light blue and white clothing.
WaldonEX is a black variant with black and red clothing.