Being fairly cheap, cheating Commander Tax for casts 3+, and having a bit of evasion makes this a competent package
Rimefire Torque joins Adaptive Training Post with that same line of text, though this time its a tap ability so its harder to keep going off
You have to sacrifice a creature every turn to keep it, which, in a token deck, is a very small price to pay
Once you start playing two or more of these a turn you'll start seeing absurd turnouts, and they're actively busted with mass reanimation like Raise the Past, Return to the Ranks, and so on
They are nearly impossible to contain and highly intelligent, featuring physiological and neural capacities similar to humans