The Idea
The idea of this deck is to take the Gruul color combo in a direction that they are not typically known for: Control! When you think of a control deck, you typically think of a deck that interacts to interrupt your opponents gameplan, while you accumulate card advantage and position yourself to play an overwhelming threat, or to win by attrition. The 60 card control strategy doesn't translate particularly well to multiplayer formats. Instead of interacting 1:1 and going for attrition, instead you want to create a state where your win is inevitable. The colors best known for accomplishing these control strategies are in WUB, so what advantage does our commander choice in the Gruul colors give us?
Our commander, Erinis, Gloom Stalker, in combination with the background Street Urchin gives us a method of interacting with our opponents from the command zone. Erinis is the only background commander that has deathtouch. Due to Street Urchin giving Erinis the ability to ping any target, the singular point of damage from Erinis's deathtouch allows us to destroy almost creature for a single mana and a sacrifice. While this sounds like a 1:1 trade, the key point of this strategy is that this interaction is repeatable, as long as you have the enchantment and the resources. Our deck also has methods of reproducing this interaction in case we somehow aren't able to keep our commander or the enchantment on the battlefield. So, lets break down the rest of the deck!
The Breakdown
We have a few avenues for winning with our deck. We can either aim to deal combat damage with our commander Erinis herself, by equipping her with Tarrian's Soulcleaver, growing her with counters while using the ability granted by street urchin, or by creating an overwhelming army via landfall triggers from Omnath, Locus of Rage or Scute Swarm. World Shaper allows us to create a large amount of landfall triggers on a moment's notice to create that army right out of the gate, along with Song of Totentanz to give that army haste. Because we are going for a control strategy, you need not create an army with an uncountable amount of creatures, but just enough to defeat your opponents, as ideally your commander will keep the board clear. Resolving a Praetor's Counsel will set up the inevitability of your win, even if you do not have the ability to win on the spot. It may just give you a second chance to do so, however, in case your plan A didn't work!
In control strategies, one of the things you need more than other strategies is a healthy number of cards in your grip, and the mana to cast them. Thankfully, the Gruul color combination is one of, if not the best for ramp. Not only that, but Erenis's second ability to recur a land allows us to use lands to create value beyond tapping for mana. If we sacrifice lands for spells or card draw, beyond our commander, we also want to have extra land drops to ensure we remain ahead on mana to be used for our generators and interaction. Augur of Autumn, Mina and Denn, Wildborn, and Crucible of Worlds give us these extra lands, or more sources to play them from. In addition to some of the more typical ramp spells, we also have Wilderness Reclamation and Seedborn Muse to untap our lands for interacting on our opponents turns if need be, or generating value before our next upkeep if we do not need to interact. The outlier in the ramp category is Crime Novelist, which is here because it refunds us the 1 mana we use on Street Urchin's ability.
In terms of card draw, we have a bit more than a typical Gruul deck would. We are not a traditional creature-based Gruul deck, so our card draw sources revolve around the few creatures we do have on the battlefield, as well as incremental, repeatable advantages. A couple of notable inclusions in this area are Goblin Engineer, which can tutor up for us almost all of the artifacts we have in our deck, included for various purposes. for the low low cost of sacrificing an artifact (token, most likely). Sprouting Goblin gives us the ability to gain card draw for lands, which we can recurve later with methods mentioned above.
Because our commander interacts primarily with creatures, we may run into some issues with non-creature based artifact or enchantment decks. We have a suite of cards in this category that do double or triple duty for our deck. Acidic Slime is an old commander staple, not only for its removal ability, but in our deck, it is a backup deathtouch creature we can use in case our commander is hated out of the game.
The "Urchin Feeder" category is a list of cards who are here to generate tokens to sacrifice to Street Urchin. The type of token doesn't particularly matter here, just the ease and repeatability of the token generation. These come mostly from either combat damage or landfall triggers. We are incentivized to attack with our commander for Erinis's land recur ability, which is made a bit easier naturally due to her built-in deathtouch, while the landfall triggers reward us for doing what Gruul does best.
Lastly, we come to the Backups and Tech category. The purpose of these cards are to either allow us to emulate the effect our commander + background pairing creates, even if we don't have our commander, or protection for our commander by keeping her alive through combat, and protection from opposing interaction. Notable, all of the artifacts here can be fetched with Goblin Engineer, giving us access to this entire suite of toolbox cards.
This deck is a work in progress!
