Grand Druid vs anything ... Grand druid. Grand druid would tear into White dragon and the white dragon would have no idea what hit him. The constant summons vs the white dragon is the killer. White dragon hands down cannot fight vs multiple enemies. Only way I see ol whitey winning is if he got a ton of ice blocks off. Question to ask is if nature boy resummons his pets while they are ice blocked, if so then ice block just works against the white dragon. Grand druid owns all.
Yulak vs White dragon ... White dragon
Yulak vs anything besides Grand druid/White dragon ... Yulak
Creature in Giant corpse that steals your weapon vs Yulak ... Would be a good fight with them stealing each others weapons back and forth .