The Deck

I'm going to break the deck down into a few sections and go over the card choices. Overall, the deck is built around Rumo, so let's start there.

The Rumo Package

If you're playing Rumo, you want a few things. First, is a critical mass of sea creatures to use his ability. Secondly, you want them to be high CMC so that you can transform him. We have a total of 11 such cards in the deck, and I found that number to be about perfect.

Koma, Cosmos Serpent is probably the most powerful, but being able to cycle Striped Riverwinder and River Serpent makes them invaluable. Not only for card advantage but for loading the graveyard, so Rumo can control what you have on top of your deck from the field. Don't forget you can cycle on your opponent's end step.

Overall, Rumo fuels himself pretty well, and the deck worked great when he was out. However, if you want to make tokens of your giant creatures with him, you must have them in play. So, let's move on to the next section.

The Reanimation Package

With so many big creatures in the deck and needing to have them in play to make tokens of them, there's also a reanimation package in the deck. It consists of ways to discard cards into the graveyard (the cycling is great here!), such as Champion of Wits, Grisly Salvage, and Consider and ways to bring them back.

Blood for Bones requires you to sac another creature (Champion of Wits is a great option because it can be eternalized from the graveyard*) and lets you reanimate something, and gives you a cycler back to hand to be used again. Lastly, we have a few copies of Liliana, Death's Majesty, who is excellent in the deck overall but is mainly there for her -3.

*When you eternalize it you get to draw and discard again... So, be sure not to miss that. 

This entire package gives the deck versatility and allows it to win games even without Rumo. Moreover, it's fully supported by what we're already doing for the primary strategy and helps reduce the awkward hands of drawing high CMC creatures. Now, I want to mention the last mainboard card - Necrotic Wound. The graveyard is so easy to fill in this deck that this is a premium removal spell. It's instant speed, and it even exiles! Who needs Fatal Push? Not us.

The Mana Base

We have a total of 23 lands in the deck, which is the sweet spot for this strategy. It's enough to make it possible to hard-cast your large creatures later in the game but still few enough not to need to be worried about getting flooded with lands too often. Both of these are balanced by how many cards you can draw. It's not too hard to draw into lands if you have one a few early lands to get your cycles or Grisly Salvage going.

On the other hand, there are many ways to discard excess land should you draw too much. There are six "pain lands" in the deck, which can be painful, but they're budget-friendly ways to have the colors you need. In the future, if you add money to the deck I would replace these first. You can swap them for Breeding Pool and Overgrown Tomb. You can also replace Opulent Palace for Zagoth Triome.

The Sideboard

Here's a small rundown of the sideboard.

• Duress - This can come in against control or combo decks where there don't play many creatures or have key non-creature spells.
• Naturalize - To remove problematic artifacts and enchantments. (These are great removing opposing graveyard hate sb cards)
• Rona's Vortex - Comes in against very aggressive decks where you need more removal and can come in Vs. Control Planeswalkers.
• Tormod's Crypt - Is cheap effective graveyard hate for any other deck using their graveyard.