A few things I think could make this go from a 4 to a 5 are adding a "NEW" mark when you pull something you don't have, an actual numbered list in the sets to see the missing spots of your collections, and perhaps an actual incentive to ranking up your badge for each set
As if that werent good enough, the Shaman can naturally kill smaller creatures like Voldaren Epicure, Sneaky Snacker, and many Elf Typal creatures in a pinch
Thats useful in any deck strategy
Take a good example at the onerous Oloro deck: Oloro is one of the most commonly played leaders out there and leads a life-gain deck that really is hard to stop, as he'll still work in the Command Zone
Mewtwo As the final boss of the original games and the star of the first Pokemon movie, Mewtwo carries enormous pop-culture weight that extends well beyond the trading card hobby
Each token comes into play tapped and attacking one of the players not being attacked by the myriad creature