Bar Waying

Bar Waying is a barrier enemy in Mega Man X2. They don't do damage directly, but can be a hazard if there is something pursuing you (and a hassle in Flame Stag's stage when you want to get the Heart Tank when the lava's chasing you!). The best weapon to destroy these is a fully charged Spin Wheel.

Drill Waying
Drill Waying is the "brother" (for lack of a better term) of Bar Waying, and it's found in Mega Man X3. It tends to drill upward and then spiral its head back down. The head is the weakness, and like with Bar Waying, it must be destroyed in order for X to pass.

Similar enemies
Bolter