Carstein Ring Battle against strigoli

[Havie]

I cant seem to get past this battle,

I can send 4-5 cavalry units at this strigoli and have them beat him for over 10min and his hp barely flinches.

Ive tried sending terrorists and a combination of heros, but no matter what this strigoli doesnt die by the time my whole army is wiped out.. I do not have spirit leech and im stuck with what units i have for this battle because of where im at in the campaign save.......... Wtf is going on here, should it really take 5 calvary units to drop this stupid wizard?

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[♔atthias♔]

what difficulty are you using

[Havie]

what difficulty are you using

Playing on normal...

I finally did it on like the 6th try or 7th try.. only thing i did different was used cain wraiths on the strigoli this time with Vlad and another few units, seemed to drop him faster, used part of the cavalry to bait some of their units around the map....... basically the exact same thing as before, idk......