TacetIrae
in terms of pre battle buffs the mage had the following in order to be able to do what he did (I am using D&D logic), first is mage armor for full body protection , protection from poison which saved him from the A's poison spit , immunity to non magical weapons which gave him protection from the long bladed weapons used by the witchers letting him handle them by hand along with haste and alacrity witch allowed him to keep up with the supernatural speed witchers have this is very much a level 20 wizard bullying some level 1 PC If ever saw it