Combo deck that either instantly exiles/mills out the opponents library, or does infinite lifeloss+lifegain depending on which creature you play it on.
The basic combo needs 3 cards, Paradise Mantle,
Freed from the Real
and then one of either
Grimoire Thief
, Siren of the Silent Song or
Servant of Tymaret
. You tap the creature for a blue mana with Paradise mantle and untap it with Freed from the Real, triggering their abilities over and over until the opponents library is gone and pass the turn to win on their draw step, or until they are dead for the Servant version.
The thief as the advantage of exiling the opponents library getting around things like Emrakul and the like, while Siren only mills it out normally but on the other hand also empties the opponents hand which should buy you some time to assemble the thief combo even in case they have some kind of millsafe. The Servant is obviously just instant death through lifeloss, which is slightly harder to stop than damage.
Turn 3 win:
1: Land, Springleaf Drum
2: Land,
Grimoire Thief
, tap for mana with springleaf, play and equip Paradise Mantle
3: Land,
Freed from the Real
, Exile library.
Well, technically you win on you opponents next draw step so it's a 3,5 turn win.
If you don't have the turn 3 win, which is pretty much every time, the best start is to lead with a Springleaf Drum and play Pain Seer turn 2 to give you card advantage.
Dimir Machinations can either be transmuted for
Freed from the Real
or a CMC 3 combo creature, or to optimize draws for Pain Seer by putting a low CMC card on top or remove things you don't need. In a pinch it can also prevent that cruical topdeck for your opponent to buy a turn, or for pure desperate digging.
Trinket Mage provides a tutor for Paradise Mantle and a small artifact toolbox that can be tuned from the sideboard. Removal with
Executioner's Capsule
, lifegain with Elixir of Immortality to offset Pain Seer, Pithing Needle to disrupt abilities or Darksteel Citadel if you need one more land.
To make the deck completely budget you simply have to get rid of the expensive lands and sideboard cards, other than that all the central maindeck cards are cheap.
A way to deal with stony silence is needed, not sure what would be best, preferably a CMC 3 card so we can tutor for it.