So I used a translator and apparently on Rooftop mission one of the enemies are the Ubvisto!! It said Chainsaw enemy.
Rooftop Mission: Mercenaries, most narrow stage. Zombies of mass occurs in the space without refuge. Enemy down with one hit every player also more than one appearance. A moment's inattention to a deadly failure alert!
※ Enemy = ヴィストヴォゥ defeat the player with one blow （ chainsaw ）
Creature Workshop: That pipeline is a large height difference of intense stage. Understand the characteristics of the stages where differences in elevation and position 突き落とせる the enemy can go in an instant, and 立ち回ろう!
This is translated from that link^
"How about you come down here and I'll show you"- Ada Wong to Derek Simmons (RE6)