This character’s card has pretty obvious abilities. As a healer, it prevents damage. He can also remove diseases in the form of -1/-1 counters. However, his disease prevents him from actively taking part in combat.
The old wizard has a few tricks up his sleeve. As we know from Forest of Doom, he can turn you into a frog. He also creates small magical trinkets to sell to adventurers to help them in their quests or he may teach them spells. This is represented by his +1/+1 counter ability.
Nicodemus does not like to be bothered which is why he goes away if you do not pay his upkeep cost and why he has shroud. Nicodemus is a retired badass wizard who now hands out helpful (usually) advice to adventurers now which is why you can draw two extra cards at the beginning of your draw step but then you have to discard one as sometimes he gets things wrong.
Using my conversion table, Balthus should have a power of 4 and a toughness of 6. Balthus makes tokens as he is rasing an army to invade the Vale of the Willow. His collection of dangerous spells is represented by his damage ability.
The Warlock of Firetop Mountain can come back to life if he is killed as long as he has body parts to bring him back. He is also able to gain control of many creatures and command them to guard his mountain or conquer Allansia.
Marr’s experiments in Marrangha where he uses the parts of captured creatures in an attempt to create the ultimate weapon. This is why he can destroy creatures. Also, if he puts more effort into his magic, he can create better beasts.
What other characters could we make into Magic cards?