Bospider is a large spider robot and boss from the first Mega Man X game. It was used to crush scrap metal before being roped into Sigma's Palace.
Bospider will go down the Kujibiki and will stop to open its red core. It'll then go up and summon mini-spiders.
Bospider will be difficult to beat without its weakness. If it goes to the space where Mega Man X is behind him, he must wall jump or dash to avoid. When its red core opens, Mega Man X must shoot it and it'll go up. When it's up, it'll summon mini-spiders, making it difficult to beat and then repeats again.