Getting a bunch of extra combat and extra power is great for decks winning through combat
Your deck is like your army, your arsenal, and your spellbook all wound up into one
The fact that you are happy to both draw (multiple?) cards due to this having 4 power, and then searching for a dragon card when it dies, makes me think this card is worth including even if you don't do any graveyard shenanigans
10 Vault of the Archangel Vault of the Archangel is an extraordinarily fun Land that not only taps for one Colorless mana, but also has the potential to stop anybody attacking you or completely change the flow of the game
There are nonbasic lands everywhere in Commander, and Primal Order is great against them
Card selection in Rakdos is another common element, whether it be through looting or rummaging. (As a brief aside, looting is when you draw a card first, and then discard a card for the second half of the spell