Whatever game aspect you need to improve whether its mana, cards in hand, or stats in play, Atraxa will help you get there
With some mana ramp like Invasion of Zendikar and removal to keep you alive like Beyond the Quiet, you should be able to crush your opponent with Atraxa
For instance, in an Archimandrite deck you could gain a bunch of life in your upkeep and first main phase to add a big +X/+0 buff to your commander, then use Alteration to turn it into Giggling Skitterspike
It only takes three defense counters to defeat, tying it for the least among the battles, which is also solid, and then the backside is fine, as a 4/4 that can make some extra mana
Essentially, a card with Imprint demands that you exile another card--it could be from your hand, from play, or even from a graveyard--that card becomes "imprinted" onto the Imprint card, and then has an effect that depends on what you exiled