Edit - immediately found the problem with Defense Grid - You want to coco at the end of the opponent's turn to combo off immediately at the start of yours. That's typically best practice. If only the mana worked I'd try Teferi, Time Raveler, but I don't think I can swing the mana for a double splash and double red, especially not if I'm worried about White Orchid Phantom, which is seeing a bit of play. So we just have to play smart, and coco when the opponent is tapped out, or only has 1 mana and we have a gut response. Still, I appreciate the comment!

I hadn't considered Defense Grid. It might be worth it, but it's a lot harder to pay 3 mana for it rather than hold up one mana and only combo off when they only have 1 mana open. I'd say matchups are pretty good against Jeskai or UW blink, but Titan can combo off before us, and we don't have a lot of tech for the matchup. We're basically preboarded for Belcher with Hexing Squelcher, I mean there's stuff you can bring in over Mogg-War Marshall, but the matchup feels good, we're a faster combo deck with answers for counterspells.

Titan is really the only combo deck (seeing play)that's faster than Goblins, and midrange decks have to compete on both axes, stopping our combo without dying to little shitters. However, faster aggro or tempo decks can beat us, ironically I'd consider Burn a really bad matchup, they just have too much removal for our Snoops and can kill us before we midrange them out most of the time. But also, I think the matchups across the board are not terrible, there's not exactly an auto-lose matchup, since fast hands can combo off as early as turn 3, and the fair midrange plan has some turn 4 kills that pop up, especially with Sling-Gang Lieutenant.

I'm assuming prowess would also be a bad matchup, as it's a fast aggro/tempo deck with lots of removal for our Snoops, but I'm not certain it's significantly worse than Burn. I also think we're especially well prepared for energy and blink, which were on my mind when I built the deck. One thing that's cool is that there's actually no good time to snipe the Snoop with removal before the combo happens, since our main combo piece with snoop is a tutor, you can just tutor for another snoop if disrupted and try again next turn. However, Consign is a big problem if the opponent lets you stack Kiki-Jiki, then counters the Harbinger, thus forcing you to draw Kiki-Jiki. And blue players are mostly on some copies of Consign, often at least 1 main even. This is why I decided on Gutteral Response over the more powerful Veil of Summer, although I'm willing to test Defense Grid over it - maybe taking a turn off to insulate yourself from Consign is worth it.