Sinitar in Heroes 5

Empowered spells mana cost is reduced by 5% and + additional 1% per hero level.

The warlocks of Ygg-Chall are dark and shadowy wizards, and Sinitar is special even among this strange group. Not only can he empower spells, but his skill is such that he can do it while using less of his own mana. No one is sure how he came to have this ability, but the scars on his face tell of bargains with the dragons of shadow -- bargains that can take a heavy toll on both body and mind.