The Goblin General has no problem holding his own against the bloated and monstrous forms of the Lord of Decay, crushing them as fast as they can disengage from battle and reach him.
He's smart as well, heading for the Plague Mothers, eliminating the source of the Demonic reinforcements. Cain keeps sending more and more to replace what has fallen before ordering the Oath Breakers to four on one the General instead of searching the city to destroy artillery.
The rate of ranged fire is already way down, enough that the demons are reaching the city without issue, but if they can't control that General, they are in danger of being pushed back.
Outnumbered by Legendary Demons, the General is hard-pressed, taking a lot of damage, but able to heal or be healed enough to hold on for now. The horns of the palace sound again, and he increases his attacks, desperately holding the Oath Breakers in combat while the next wave of forces charges.