Not only does he let your Defenders attack as though they didnt have Defender not only does he give you the damage according to toughness ability he also gives you a source of hand refill with his final ability
Essentially, you cast Amulet of Quoz, sacrifice it after a whole turn, and bet the outcome of the match in a coin flip
Cost reduction will allow you to get cards like Karametra, God of Harvests, Reki, the History of Kamigawa, and Gandalf the White out early in order to capitalize on their ramp, draw, and synergy
It's a very nice mechanic, as it grants these creatures a lot of flexibility
You can cleave it as an alternate cost, and then you net a free spell for the turn, and I love it on an enemy's turn when you cast this for free, to bounce what your foe played and then drop a flash thing like Hullbreaker Horror or Ancient Stone Idol or you can just cast another instant that draws you cards
Most cards nowadays have an expansion symbol on the right side in the space between the text box and the art