By casting noncreature spells, Im able to raise my prowess blockers toughness high enough that I wont take excess damage from any trample attacks
In the right deck, youre already wanting to cycle or discard cards, and this allows you to repeatedly create 1-mana 2/2 fliers, which is a good rate no matter which format youre playing
The loss of life and card advantage allow Vampiric to reasonably just cost one which in turn allows you to keep even one land hands if they are good enough and you have Vamp to get you out of it
Some cards have a version name listed under them, like Stitch - Covert Agent. Ink: The color band and symbol underneath the cards name shows its ink type
Which in turn makes them one of the most popular Commanders overall, and strong enough for cEDH
The timing will be specified in the card, or it will be implicit because of the card type