Unlike other sources of ramp, like creatures or artifacts that tap for mana, lands are very difficult to remove from the battlefield, and unlike temporary ramp, like Dark Ritual, extra lands continue to provide an advantage turn after turn
It also works well in milling decks as a way to mill while doing something useful
You can of course use all three choices to draw three cards, or you can use it to counter an opponents spell and draw two cards, or pick one of each
Marath, Will of the Wild pushes for a big mana spin on tokens, with its weird activated ability to go along with that, while Gahiji, Honored One has a political bend to its ability
Let me know down below, or hit us up on the Draftsim Discord
As a five-mana 4/2 that discards your hand and draws three cards, the Ox is okay