The ability to pay mana and ping each opponent isn't incredibly powerful, but it is a way to keep things rolling in decks such as Rakdos, Lord of Riots or the more recent Ob Nixilis, Captive Kingpin without having to have spells or other nonland permanents around to help generate life loss
If you draw it off the top, odds are you'll have some use for it to cast a big demon or a smattering of cheaper spells
Then amass Orcs X, where X is the number of instant and sorcery cards in that player's graveyard
They are all in the flavor of Ophidian, and they are flying 1/3s, or grounded 1/3s, or fear 1/3s, and such all over
Archangel of Thune is among the strongest, turning each instance of lifegain into a buff for your entire team