Yort

 Yort is a virus from the Mega Man Battle Network series. This virus shoots out a yo-yo from itself, launching the yo-yo along the row which eventually comes back to itself. Variants shoot the yo-yos out faster as the levels increase.

Yort
 Yort s are white and purple with green eyes. They shoot red yo-yos.

Yurt
 Yart s are yellow and black with red eyes. They shoot green yo-yos. These launch their yo-yos much more frequently than Yorts.

Yart
 Yarts are white and yellow with purple eyes. They shoot blue yo-yos. These launch their yo-yos much more frequently than Yurts.

YortΩ
 YortΩs are white and black with blue eyes. They shoot yellow yo-yos.

BigYart
BigYart is a miniboss in Mega Man Network Transmission  found in No Grav Zone. There are three yo-yos that circle around the miniboss as it hovers up and down, acting as shields. The only vulnerable spot of this miniboss is a tiny opening in the middle. It also shoots out homing missiles that can damage its target. Those missiles can be destroyed.

Source
Sprite images found at Sprites INC