Having been around since the beginning of the game, artifacts have proven themselves to be some of the strongest cards out there and decks that focus on this archetype, and can pull it off, have historically been some of the strongest in the game, as is the case with modern Affinity. I’m not sure why this deck is called Affinity, because none of the cards in it actually have the affinity mechanic. As you read on, keep in mind that artifacts are typically colorless so they are not bound by the dogma of the color pie in terms of what they can and cannot do.
The CMCs (converted mana cost) of the cards most commonly seen in Affinity range from 0-3. That’s very good considering modern games typically only last an average of about 4-6 turns. Let’s start at the bottom of the curve with Ornithopter and Memnite. Both are artifact creatures that cost no mana at all. Ornithopter is a 0/2 with flying while Memnite is a simple 1/1. Alone, these two are not very threatening so lets move on to the next card in the curve, Signal Pest. Signal Pest is a 0/1 for 1 mana. It also has the keyword battle cry. When a creature with battle cry attacks each other attacking creature gets +1/+0 until end of turn. Not that powerful, but it can certainly be effective. It turns the Ornithopter into a 1/2 flyer and Memnite into a 2/1 when they attack.
Another card to quickly mention before we get to the good stuff is Vault Skirge.Vault Skirge costs 1 generic mana and 1 black phyrexian mana which can be paid for with 1 black mana or 2 life. Early in the game, 2 life is nothing so it’s no big deal to play this for 1 mana by paying two life. It also gets bonus points for having the keyword abilities flying and lifelink (yes, that means if you attack with this boosted by Signal Pest it will pay for itself on the next turn if you used its phyrexian mana cost).
In the 2 mana slot things start to get silly. Arcbound Ravager is a 0/0 creature that has modular 1, meaning it comes in with a +1/+1 counter and when it dies, we can move all of the counters on it to another artifact creature. We can also feed it artifacts to add more +1/+1 counters to it. This can make it a huge threat that our opponent has to answer (probably with removal that will kill it) and when it dies another creature becomes the threat.
Steel Overseer functions similarly to a tribal lord for artifact creatures. All we have to do is tap him to give each artifact creature a +1/+1 counter. What breaks this card is the fact that it is possible to play it on turn 1 so it can pump our Ornithopters and Memnites on turn 2.
Etched Champion and Master of Etherium are in the highest slot of the deck. Etched Champion is a 2/2 for 3, which is terrible compared to other creatures, but as long we control three or more artifacts it has protection from all colors due to its metalcraft ability. That means it cannot be targeted by colored removal or dealt damage from colored creatures so it’s more than just a 2/2 for 3; it’s a 2/2 for 3 that is nearly impossible to get rid of.
In most tribes, there are lords that boost their tribe and there are creatures that get stronger the more creatures of that tribe you control. With Master of Etherium you get both. Not only does it give +1/+1 to artifact creatures, but his power and toughness are also equal to the number of artifacts you control.
Other artifacts that the deck runs are Mox Opal and Cranial Plating. Mox Opal is another 0 cost artifact that can tap for any color of mana if its metalcraft ability is online (active). Cranial Plating is an equipment that costs 2 mana to cast and 1 to equip. It gives the equipped creature +1/+0 for each artifact you control. Now equipment can only be equipped and unequipped at sorcery speed, but Cranial Plating can be moved at instant speed for 2 black mana. This means you can move it after your opponent declares blockers allowing you to deal a ton of damage to them or at least kill their most threatening blocker if they block everything.
Some other threats in this deck include Blinkmoth Nexus and Inkmoth Nexus. These are both lands that can animate into 1/1 flying artifact creatures. The only difference is Blinkmoth Nexus can give a creature +1/+1 for 1 mana while the Inkmoth Nexus creature has infect. The strategy here is to animate the Inkmoth Nexus and use the Blinkmoth Nexus to give it +1/+1 makings its infect a little stronger (as if Steel Overseer, Cranial Plating, Master of Etherium, and Signal Pest aren’t enough).
Side Board: Like all side boards, it should be tailored to your local meta. This is also not a complete deck list so feel free to main board and experiment with some of the following cards. Galvanic Blast is a great option that most Affinity decks run in the main board. It can function as a Shock or a better Lightning Bolt if you have metalcraft as you most likely will. Dismember is a good option for more removal or combat tricks as well as Grasp of Darkness. Karn, Scion of Urza can be a good inclusion because it grants some card draw or puts more artifact creatures into play. Tezzeret’s Touch could be an interesting option for animating a Mox Opal. Tormod’s Crypt will side in nicely against graveyard decks since it costs 0.
Since most of the cards in the deck are colorless, you can afford to be flexible with your experimenting and not have to worry too much about colored mana, especially since Mox Opal can produce any color.
The basic shell of Affinity should look something like the following:
2-4x Vault Skirge
3-4x Signal Pest
4x Steel Overseer
2-3x Etched Champion
2-3x Master of Etherium
4x Mox Opal
2-4x Cranial Plating
4x Blinkmoth Nexus
4x Inkmoth Nexus
Note: There should be a minimum of 6 copies between Memnite and Ornithopter, with 8 being ideal.
Once again, this is not meant to be a complete deck list. It’s more of a guide to understand how the deck functions and a look at the key cards behind it, the purpose of which is to help newer players decide if this sounds like something they want to build or get an idea of how it runs and figure out a way to beat it. What else do you want to learn more about? Let me know in the comments below.