Good-Fortune Unicorn provides blanket +1/+1 counters to everything[/card], and Grumgully, the Generous does the same for non-humans
From a competitive standpoint, Whispers in the Well added a ton of competition-ready cards and shook up the meta nicely following Fabled's laying the foundations and bringing in new waves of players.
Aethersphere Harvester has Flying and "When Aethersphere Harvester enters the battlefield, you gain two energy tokens"
For example, if Strata Scythe's imprint ability ("When this Equipment enters, search your library for a land card, exile it, then shuffle.") triggers twice (probably because it somehow entered attached to Cloud), up to two total land cards can be exiled
8 Conclave Evangelist Many, Many Elephants In The Room Myriad is fantastic for multiplayer games, allowing you to damage all opponents equally instead of focusing down a single player
But it was printed at a lower rarity than other commons and was just one/sheet