The deck
Putting this deck together was an exercise in reverse-engineering.
To start, Sierra needs three copies of Brassbug Hive (R) as her win-condition.
She wants to run three copies of Mechanical Training (C) to close out the game with Brassbug Hive, but they also need to not be dead cards before a Brassbug Hive is online. This means including some combination of Armored Jammer, Haven, Bravos Bastion (R), The Foundry, Axiom Bastion (R), Axiom Reprocessor (R), and The Ouroboros, Lyra Bastion (F).
Sierra also wants to be able to dig through her deck to find her Brassbug Hives on time. This makes The Ouroboros (F)’s filtering, The Foundry (R)’s card draw, and Axiom Reprocessor (R)’s passive resupply particularly compelling.
I think the most competitive option is The Ouroboros by virtue of being a 3-mana permanent you can play on D1 for a Brassbug. It digs two cards deep and can get Brassbug-creation support abilities directly into reserve. I like Taytwo’s list a lot.
I thought it would be fun to go with The Foundry. Costing 4 mana hurts, but it has the advantage of triggering your from-reserve abilities to recoup the tempo loss and can draw your Brassbug Hives into hand, where they can’t be sabotaged.
Including The Foundry means you’ll also want to bring along Foundry Armorer (C), Axiom Salvager (C), and Ada Lovelace (C) to make the most of it.
But the biggest draw of The Foundry is enhancing your sabotage. Haven Bouncer (F) becomes a tempo-positive play, Tinker Bell now sabotages from hand and reserve. Including both means you can repeatedly wear down your opponent’s resources. If you can keep them low enough on cards, you can make it more costly for them to hold onto removal for your Brassbug Hives.
There’s a conflict between supporting The Foundry with from-reserve abilities and supporting Brassbug Hive with support abilities. Both eat up rares and bloat the 3-mana slot.
Uniques
Baku: 5/7
Where common and rare Baku sacrifice tempo to attack your opponent’s resources, this unique requires no such trade-off. You generate 6/6/6 in stats across both expeditions that can be boosted by a Brassbug Hive or Ogun. Often, this is played a point in the game when your opponent is only holding one or two cards, so the discard over two consecutive turns can really hurt.
This shares the downside of any expensive unique. Costing 6 means it competes with Sierra’s D4 Brassbug Hive unless you’re able to play the Hive ahead of schedule. Still, this is the kind of unique that makes tapping out pretty compelling.
Foundry Armorer (U-2163): 5/7
This one is a strong on-curve play that will usually guarantee a trade on D2. It can be a finisher when paired with a Brassbug Hive or Ogun, and it gets a benefit from The Foundry.
Foundry Armorer (U-2367): 6/7
This is a unique worth running The Foundry for. 3 mana for 7/6/7 across three bodies is already incredible, but this also sees its own token-creation triggers, meaning you can discard up to two cards from your reserve for +2/2/2 each, or more if you already have any Brassbugs out.
Takeaways
The current card pool limits how many Foundry payoffs you can include in your deck. I’m excited to revisit this build once more from-reserve abilities are released.
Ideally, the deck’s uniques should not be Foundry Armorers since they prevent you from running copies at common, which is one of the draws of The Foundry in the first place.
I overlooked Armored Jammer when building the deck. Committing even harder to sabotage by turning Mechanical Training (C) into a sabotager looks pretty sweet. I’m curious how many copies I can get away without making the deck’s early-game even worse.
The games
Round 1 (W): Treyst & Rossum
I led with an Inari (F), but my opponent had an incredible start of a Haven, Bravos Bastion (F) that resupplied into an Axiom Salvager (R), which itself resupplied into a second Haven.
I went 0-2 with a Brassbug Hub (C) and Foundry Mechanic (C) on D2 while my opponent set up their second Haven and played two 1-drops, one of them double-boosted.
Fortunately, I was able to spend the Foundry Mechanic’s support ability to get down a Brassbug Hive (R) one turn early. I judged getting my win-condition online more important than sabotaging my opponent’s Ada Lovelace (R) in reserve with a Haven Bouncer (F). I stacked my Brassbugs on side to play defensively against double Haven. My opponent Kelon Burst (C)-ed my Brassbug Hub which hurt, but at least I didn’t have to spend my Inari support ability just yet.
On D4, I managed to draw and play my second Brassbug Hive (R). This time my opponent applied enough pressure to force me to cash in the Inari support ability for a double-boosted Brassbug. Awkward regions for my opponent’s mountain-heavy characters meant I was able to win a much-needed 2-0.
My two Brassbugs at noon and both sides of a Mechanical Training (C) helped me barely trade on the following turn once Treyst was spewing out double-boosted characters. A key Haven Bouncer (F) sabotage on their Dr. Frankenstein (R) slowed their progress by just enough.
An Inari (R) and Foundry Armorer (C) with the passive Brassbugs combined for a massive 15/15/15 on one side. My opponent’s Anansi (U) had boosted for their three cards in reserve plus the Haven boosts to block that side but not advance. My opponent resupplied into a Kraken’s Wrath (F) but was below the mana to use it. This meant I was able to barely push the other expedition through, again thanks to mountain not being active.
On the final turn, we were at 1/2 on expeditions. My opponent played around sabotage as the first player and immediately used Kraken’s Wrath (F) to scoop up my two noon Brassbugs. I didn’t have the sabotage, and I played a Mechanical Training (C) to generate two more 4-4-4 Brassbugs to overwhelm one side. My opponent didn’t have ways to get more cards into reserve and wasn’t able to stop me.
Had my opponent been greedier with their Kraken’s Wrath (F), they would have been able to 2-0 me for the win.
Round 2 (W): Teija & Nauraa
My opponent’s Spindle Harveters (C) and unboosted Lyra Thespian (F) were able to 1-0 against my Inari (F). I set up The Foundry, Axiom Bastion (R) on D2. This earned me an 0-2, but I was glad that my opponent had to spend two Lyra Thespian (F)s to achieve this.
On D3, my opponent replayed their Spindle Harvesters (C). Knowing how important anchored and boosted characters are for Teija, I was content to Kelon Burst (C) it.
They won one side and anchored a Lyra Thespian (U), but I was able to take the other with an Ada Lovelace (C), activating its from-reserve ability with The Foundry to put a Brassbug Hive (R) into reserve and draw a card. I felt comfortable doing this even as the second player next turn because my opponent was Muna, so I wasn’t afraid of sabotage.
On D4, playing the Brassbug Hive (R) and stacking both Brassbugs diagonal to their Daughter of Yggdrasil (R) ensured a trade. My opponent was ready with a Mana Reaping (C) on the Brassbug Hive.
Thanks to my opponent ramping me with Mana Reaping, I was able to sabotage their Daughter of Yggdrasil (R) with a Foundry-activated Tinker Bell (R), then play a replacement Brassbug Hive (R). They had the Cloth Cocoon (F) to remove it again, but this time I got to 2-0.
On 9 mana, my face-up Tinker Bell (R) pressured my opponent to play out their Lyra Thespian (U) without its trigger, only for the Tinker Bell to sabotage the other card in their reserve, a Meditation Training (R).
My opponent played their second-to-last card in hand, upon which I hit them with my Baku (U), which put me ahead in both expeditions and sniped the last card from their hand to 2-0 again.
On the next turn, Baku (U) hit one of the two cards they top-decked. This left them without ways to spend their mana and let me play out my hand for the win.
Round 3 (L): Fen & Crowbar
I took an easy 1-0 against a slept Kodama (R) on D1. They anchored out an Aloe Vera (F) on D2, and I was okay going 0-1 to Kelon Burst (C) it.
My opponent had an incredible D3. They first played a 2-mana Anansi (U) that let them put a card into hand to boost for each card in each player’s reserve. They put a Martengale (C) into reserve, then used the support ability and their three remaining mana to anchor out an Aloe Vera (F), winning both sides. To make matters worse, their Kodama (R) support ability let them anchor out their 7/8/8 Anansi (U).
They resupplied into a Cloth Cocoon (C) on D4, which was a problem for the Brassbug Hive (R) I was about to run out. Fortunately, my opponent spent 4 mana for Flamel (F) to pick up the Cloth Cocoon. This meant I couldn’t sabotage it, but I was now free to run out my Brassbug Hive (R). The anchored Anansi (U) and Aloe Vera (F) helped my opponent 2-0 again. Their Ouroboros Inkcaster (R) even let them return the Anansi (U) to hand.
Seeking to maximize their cards, my opponent put their Cloth Cocoon back into reserve with their Anansi (U), which opened it up to being sabotaged by my Haven Bouncer (R). I’m not 100% this was better than playing a second Brassbug Hive for tempo to force my opponent to spend 3 mana for Cloth Cocoon. As it was, I managed a 1-1, but my opponent was able to anchor out an Aloe Vera for the next turn.
I got down the second Brassbug Hive (R) but didn’t draw into anything meaningful to play alongside it. My opponent’s Aloe Vera from the previous day along with an Off You Go! (F) on one of the double-boosted Brassbugs helped them easily take one side.