Not all units exept the footman can make the animation but the ability is very simple, copy and paste the defend ability, then, change the move speed factor to 20 (if too slow rescale it) and change the magic damage reduction to 0, change the damage taked to 0.80%, leave the damage dealt to 1.00 and (optionally) change the reduction chance, the race and some misc for the ability (since change it will be a wast of time)