UB Mill Deck

this deck is based on a mix of milling the opponent and using cipher with deathcult rogue to hurt the opponent and power up creatures like jaces phantasm and consuming aberration. this is my first deck since coming back from casually playing around 5 years ago and ub has always been my favorite mix of colors. i was thinking about adding some cards like snapcaster mage, jaces phantasm, dimir charm, consuming aberration and nightveil specter. any helpful tips are highly appreciated. i know ub decks arent very competitive, so i was also thinking of adding a color (maybe green) and get some helpful spells to protect my creatures in order to gain some competitiveness in this deck.