I think if you want to support Flash as an archetype, especially at 720, you need those "worse Pestermites" to fill it out. Otherwise you just end up with a Simic deck that happens to have one or two flash cards. After doing the yearly comparison for the average MTGS cube for a few years now, I can't disagree more on how deep the peasant card pool is beyond 450/540. Even at 360 I still have several cards that I'm looking at replacing with upcoming new releases.
I do like the flash -2/-0 creatures, but I don't like it on a 1/2. It's hard to take advantage of the power reduction to use that as a trick unless you already have some sort of board presence. That's why I like Nebelgast Intruder. Despite being priced at two more mana, the two power plus flying really helps to turn it into a pseudo removal spell.
As for Infiltrator and Shinobi, I believe you'll need both if you want to push Ninjas as a UB archetype. Unfortunately, Ninjutsu isn't a very fleshed out keyword for peasant legal cards. Only five or so in blue and black that are worth running, imo. I'd also look at running some of the cheap unblockable creatures in both blue and black to help get those ninjas on the board.
First and foremost, I think it's really tough to make a linear archetype like flash viable at such a large cube size. I'd say that's doubly true at peasant where, despite all the bangers we've gotten the last few years, the card quality still starts to fall off pretty quickly after the 450/540 range.
With that said, I do love UG Flash as an archetype. It's fun to play and super annoying to play against. With Spellstutter Sprite, I think you also want Faerie Duelist and Faerie Vandal. Threnody Singer and Nebelgast Intruder are good combat tricks for the flash deck. Scion of Stygia, Breaching Hippocamp, and Illusory Ambusher are other cards I'd be looking at in blue to support a flash archetype. There a ton of french vanilla flash flyers, but I think I'd stick with a tempo game plan. For green I think Ambush Viper is great as "removal" for the deck. I also like Briarpack Alpha and Pack Guardian as top end cards. I don't like the 5+ mana options that much, since you're mostly looking at a tempo/midrange deck. In gold Fleetfeather Cockatrice could be one of the few 5+ mana creatures I'd look at. Deathtouch is nice for the removal aspect and it can help to close out the game and take advantage of potential flood. Other than that, Horizon chimera and Winged Coatl are both decent filler to help increase density.
You mention ninjas as well and I think you could have some really nice cross-pollination between the two archetypes and try to go a little deeper in UB with ninjas as the tempo deck of choice, especially since your list is larger.
I do like the flash -2/-0 creatures, but I don't like it on a 1/2. It's hard to take advantage of the power reduction to use that as a trick unless you already have some sort of board presence. That's why I like Nebelgast Intruder. Despite being priced at two more mana, the two power plus flying really helps to turn it into a pseudo removal spell.
As for Infiltrator and Shinobi, I believe you'll need both if you want to push Ninjas as a UB archetype. Unfortunately, Ninjutsu isn't a very fleshed out keyword for peasant legal cards. Only five or so in blue and black that are worth running, imo. I'd also look at running some of the cheap unblockable creatures in both blue and black to help get those ninjas on the board.
MTGS Average Peasant Cube 2023 Edition
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With that said, I do love UG Flash as an archetype. It's fun to play and super annoying to play against. With Spellstutter Sprite, I think you also want Faerie Duelist and Faerie Vandal. Threnody Singer and Nebelgast Intruder are good combat tricks for the flash deck. Scion of Stygia, Breaching Hippocamp, and Illusory Ambusher are other cards I'd be looking at in blue to support a flash archetype. There a ton of french vanilla flash flyers, but I think I'd stick with a tempo game plan. For green I think Ambush Viper is great as "removal" for the deck. I also like Briarpack Alpha and Pack Guardian as top end cards. I don't like the 5+ mana options that much, since you're mostly looking at a tempo/midrange deck. In gold Fleetfeather Cockatrice could be one of the few 5+ mana creatures I'd look at. Deathtouch is nice for the removal aspect and it can help to close out the game and take advantage of potential flood. Other than that, Horizon chimera and Winged Coatl are both decent filler to help increase density.
You mention ninjas as well and I think you could have some really nice cross-pollination between the two archetypes and try to go a little deeper in UB with ninjas as the tempo deck of choice, especially since your list is larger.
MTGS Average Peasant Cube 2023 Edition
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