Shiki no Uta (Muldrotha EDH, Seasons Past Control) (EDH / Commander)

BUG Seasons Past control deck, with Muldrotha on the helm.

The main strategy is to play the long game. Ramp strong, draw millions of cards, kill everything, repeat.
Seasons Past is the centerpiece of the deck. It converts all of our used up removal and tutors into more action. The trick is to recur at least one tutor, so that it can fetch back Seasons Past.
Muldrotha functions as a value engine in the midgame. She lets us get back any permanent that might have been blown up earlier, including our own fetches. Later in the game she functions as a backup Seasons Past, for permanents like Nihil Spellbomb, Seal of Primordium, and Pernicious Deed. She can also recur any of our wincons should they fall.
Muldrotha offers some advantages over Tasigur, the traditional Seasons Past control commander. For instance, you get to choose which cards to get back from the graveyard. Additionally, her ability has no activation cost, which eases a bit on the mana. The downside is, of course, she cannot get back instants/sorceries, and is overall more expensive and difficult to cast.

If your meta is heavy on grave hate, consider Riftsweeper. Card choices in the deck are heavily dependent on your meta, but overall Muldrotha likes permanents over spells.