blue green oath is by far the best of all the oath variants. with it you can stop aggro with weevers/core/feeders, have counters to stop annoying things from mindtwist to keg to animate dead, and also recursion to get all the stuff back. with the board, you can go with b2b to stop all the multi color decks. as for what you need, obviously oaths ( ) core, weever, morp, feeder, fow, drains, misD's, trops, islands, forrest(not many tho), blessings, um, there is more, but thats the git for now

check some of the decklist on the site for more info