All early playing cards were single headed (also called single ended)
The worst grade you can get for centering is a 4 but if the card exhibits the features of a higher grader except centering, you'll have the chance at a grade 9 with the OC (Off-center) qualifier
With that, let's look at the abridged deck tech
The only really viable deck for the Treasure Mage is a big mana artifact deck for which there are so many options on very powerful cards the Mage is frequently sidelined
Malamet Veteran Four generic, one green, Creature - Cat Warrior - 5/4 - Common Trample Descend 4 Whenever Malamet Veteran attacks, if there are four or more permanent cards in your graveyard, put a +1/+1 counter on target creature
Like the split cards from the previous set, it can be cast with either spell when cast