The first is that it enters the battlefield untapped, letting you use it right away, such that it only costs a virtual one mana to deploy provided you can make use of the mana it provides immediately
You can drop them early or free any time to break folks faces, and good free stuff is always good, but many in Commander might go with the 4/4 Wurms first in a Commander brew with 40 life to get too and trample too
The ability also triggers if our opponent targets it with a spell, which makes it somewhat resilient to removal
That said, Id resist the temptation to stick some of the zero-drop artifact creatures like Ornithopter in
3 and Garland, Knight of Cornelia Black Mage Aggro is WotCs title for this one, but Id classify this as more of a bleeder archetype if anything
This three-ink card has a strong effect when it comes into play, one that is pretty unique even now