Bospider

Bospider (portmanteau of "boss" and "spider") is the giant spider boss at the end of the first section of Sigma's fortress in Mega Man X1. It sends out mini spiders and creates random paths down its four poles, so the player must stay on the move. Its main weakness is Shotgun Ice, but it is difficult to hit the boss with it (or the Hadoken) in time to hit the red dot on its back when it appears.