Pit fiend

Scholars pertain that there are sixteen standard ranks of baatezu and pit fiends are right at the top of this hierarchy.

Pit fiends are the generals of baatezu armies, the orchestrators of mass corruption and the bullies of their lesser devils. They appear as bestial, scaled humanoids twice the height of any human being with a pair of wings that it can wrap around its body. As venom drips from their fangs, fire wreathes the pit fiend's entire body.

Armed with superhuman combat prowess, the intelligence of a mighty wizard, an array of powerful spell-like abilities and usually the resources of a devilish army as well, pit fiends are incredibly dangerous foes. Powerful conjurers can summon a pit fiend to make deals. Contracts are usually written up in order to have the deal honoured, but pit fiends are masters of such things and always have ways of perverting the contract to their own ends.

The next step up from pit fiend in the infernal hierarchy is the rank of duke. Only dukes are allowed to become an archdevil. The process of becoming a duke does not involve a ritual as other devilish ranks do; it just means that a pit fiend gains even more prestige.