U/B Covetous Control (Arena Bo1) (Pioneer)

This is a viable control deck in Standard, using Blue and Black.

The key interaction for early game is Vicious Rumors, which starts filling the graveyard on turn 1 and or 2. This immediately powers up Drown in the Loch, which is the main swing card for the deck. As it is both a counter spell and a creature removal spell, the majority of the other spells support that either as counter spells (Convolute and Didn't Say Please) or as removal (Tyran'ts Scorn, Epic Downfall, Legion's End).

Thought Erasure helps pull critical cards out of their hand, not only to keep your opponent from using them, but in their graveyard it is still a viable target for your Covetous Urge.

A single Mnemonic Betrayal is an excellent late game swing card, as it can either take advantage of many of their low cost spells and creatures or for a single powerful finishing card.
Covetous Urge also brings you game finishers from their deck.

Since the rest of the deck is literally about controlling your opponent and beating them up with their own cards, Etrata, the Silencer is skulking around and forcing yet another potential win condition.

Drawn from Dreams keeps your game from stalling out, and allows you to keep stocking your hand with critical spells that can support your game in all modes. I can help you catch up, it can help keep you ahead, and it even can help shore up a game that is on the flux point.

This deck sees many scoops in Arena. It often has obnoxious wins, and very satisfying when you beat your opponent with their own bombs.

Like any control deck, if they can get ahead of your control or get down planeswalkers when you are not in a position to prevent it, then they can often turn the corner on you.
The early game in this deck is fast enough and deep enough to handle White and R/W life gain decks, and elemental decks. Red aggro can get under this if they have a great starting hand, but this deck can even shread that if you have Vicious Rumors, Thought Erasure and one or two counters/removal in your hand. This happens quite often.

One of each; Castle Locthwain and Castle Vantress can help support mid to late game, and have been responsible for keeping this deck in the game when it grows into a long game in a stalemate.