Muldrotha (EDH / Commander)

Early you can ramp quickly and there are many cards that allow you to play additional lands (Azusa, Lost but Seeking, Exploration, etc.)
Most of your threats to close the game use the Landfall ability so the additional lands played will multiply their effects.
Try to fill your graveyard with self mill cards like Vessel of Nascency and Life From the Loam's Dredge ability.
You can use removal, counters and other useful effects and because they're all permanents you can play them again from the graveyard with Muldrotha, the Gravetide's ability to reuse them.
With the commander and a few similar effects (Crucible of Worlds) you can play lands from the graveyard, which benefits a few other powerful cards (The Gitrog Monster, Titania, Protector of Argoth) as well as landfall triggers.
Because of how strong the deck becomes once Muldrotha is out you'll want some ways to protect them, like countermagic on creatures (Voidmage Prodigy) or using Kaya's Ghostform which will return them when removed, then you can just play these protection pieces again using Muldrotha's ability making them much harder to deal with.

Additionally the deck runs combo cards to summon Marit Lage, an indestructible flying 20/20 creature and with Muldrotha you can easily recreate the combo again when its removed (you can only have 1 of this creature at a time).
To summon you preform a two card combo, play Dark Depths, which comes in with ice counters, and rather than paying to remove them you can cheat around the cost two different ways,
1: You can copy dark depths with Thespian's Stage, which will copy the card but not the counters causing the Thespian's Stage Dark Depths to automatically sacrifice itself (note you must also sacrifice the original Dark Depths along with Thespian's Stage because you cannot control two legendary permanents of the same name).
2: You can remove the counters by playing Vampire Hexmage, then using its ability to sacrifice itself to remove the ice counters from Dark Depths.
Once Dark Depths is sacrificed from having no counters you put Marit Lage into play.

Note Using Muldrotha Efficiently:
If a card is multiple types you can declare which one you are using in a way that lets you play more cards, you can play a creature like Coiling Oracle, but also play a second creature if it is an artifact creature like Baleful Strix by declaring it as your artifact for the turn, but this will stop you from playing other artifacts for the turn from the grave. There are a few cards with multiple types for this benefit.

Note Dredge:
Dredge N (If you would draw a card, instead you may mill N cards. If you do, return this card from your graveyard to your hand.)
So for Life from the Loam you can say, instead of drawing for this turn I want to put Life from the Loam back into my hand and mill 3 cards.

Neat interaction with The Gitrog Monster:
Not as important as everything else but if you end your turn with more than 7 cards in hand when you discard a land from your hand The Gitrog Monster will cause you to draw another card which will put you over 7 again and you can use this interaction to put any amount of lands from your hand to the graveyard and draw new cards.