I dont know if the dev team would be able to implement a new boss anytime soon but i think a Giant Spider Boss would make sense since we allready have the King fleshpound and the abomination.
Special abillitys of the spider boss could be:
Can climb walls and ceilings
Lays eggs that spawn spiders after some time if not destroyed
Shoots spider webs that slow players down if they walk into them but they burn very easily.
Spits poison
Whenever it gets hurt enough it climbs on the ceiling somewhere and waits for a player to walk below it to jump on and heal itself like hans.
Special abillitys of the spider boss could be:
Can climb walls and ceilings
Lays eggs that spawn spiders after some time if not destroyed
Shoots spider webs that slow players down if they walk into them but they burn very easily.
Spits poison
Whenever it gets hurt enough it climbs on the ceiling somewhere and waits for a player to walk below it to jump on and heal itself like hans.