If your HE opponent is bringing Tyrion vice Teclis, rejoice since he is unlikely to have a high level wizard as well since Tyrion is very expensive. A scar vet on a cold one with GW, dragon helm, dawnstone and the other trickster's shard should work. Tyrion has flaming attacks so between the AS re-roll and 2+ vs flaming the SV should survive. On the offensive side, the S7 attacks back forcing Tyrion to re-roll ward saves should allow a wound to get through per turn. To really make sure, get static combat res working in your favour as Tyrion is not stubborn and the easiest way to kill him is to run him down.
Edit: as per later post, trickster's shard won't work since Tyrion has regen so replace with venom of the firefly frog.