Which of those get higher priority and do not work with each other?
Winter Wyvern strikes the battlefield with a maddening chill, cursing
a targeted enemy unit and freezing it in place. All of the target's
nearby allied units will go into an uncontrollable frenzy, attacking
the frozen ally for a short duration.
vs
Calls the targeted enemy for a duel. Both you and the enemy will be
forced to attack each other and will both be unable to use items or
abilities. The victor gains permanent bonus damage.
vs
Mogul Kahn focuses all of his enemies' hatred on him, causing them to
attack him at all costs.
Best Answer
When Berserker's called, a Dueling unit will attack alternatively Axe and his Duel opponent, canceling animation everytime due to the very low attack interval Berserker's call and Duel force.
In a similiar fashion, the hero under Wyvern's Winter's Curse will attack alternatively both the frozen ally and his Duel opponent, canceling his attack everytime. If you add berserker's call on top of that, it can either :
This alternative fashion come from the way the buffs work. While under one of those buff (Ill take Berserker's call for example) the buffed Hero trigger and attack versus axe every 0.25 sec. However the attack action itself can be overwritten by a triggered attack toward another target forced by one of the other buff. Thus your hero will alternatively change target. Depending on when the buff are applied (e.g. if the frequency of attack for either of those 3 buff is synched with another) the interaction between those spells become very weird.
If your hero has a really low attack rate (such as Alchemist with +Attack Speed items), you can attack fast enough to perform an hit on both target alternatively.