This is the deck I've been using at FNM for the better part of two years at my local FNMs when I'm not trying some janky brew. It has changed slightly since its inception, but the core of the deck is the same. Prowess creatures, hit face, green more fun than blue, SMOrc.
More seriously, this deck is a mostly red aggro list, that splashes green to capitalize on Atarka's Command, BBE, and a few sideboard cards. It is incredibly good at grinding out midrange decks if push comes to shove, and it has reliable turn 4 kills through interaction against control decks (and a couple sneaky turn 3 kills).
Monastery Swiftspear, Soul-Scar Mage, and Bomat Courier are our premiere 1-drops. Ol' Reliable is blocker removal and face damage. Atarka's Command can deliver a whopping amount of damage if your creatures go unchecked. Burning-Tree Emissary is a free creature, Mutagenic Growth is a free spell, and Reckless Bushwhacker likes both. Ancestral Recall is our main card draw. Bonecrusher Giant counts as both extra removal spells and threat density when we need it. Our top end is three BBEs with a fourth in the side. (In the past I have also run an Escape to the Wilds for the really grindy matchups, but I'm less hot on it now.)
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Some sequencing/play pattern things:
-Light up the Stage can hit two lands sometimes, so if you think there's a chance you'll need both land drops, then you can't play a land before casting it.
-Sometimes casting a bolt for the spectacle cost precombat is enough for exact lethal if you hit a playable spell, so make sure you count it.
-If your opening hand has two creatures, a mountain and a LutS, you can keep the hand, but you need to play the non-hasty creature on turn 1 if you have one, so you have 2 creatures to swing with on turn 2 for spectacle.
-If you have a bomat courier, play it on 1 with very few exceptions. This card has such incredible value stapled to it that players will be forced to kill it quickly. If it dies, then a prowess creature lived. The only time you should hold it that I can think of is the previous LutS scenario where you have to play soul scar mage on 1 to guarantee spectacle with two attackers.
-Bluffing a mutagenic is a great way to trigger LutS. Bomat courier gets a lot of free swings in because people fear losing their 1 drops.
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When sideboarding, know your role in the matchup:
-Versus control, you often need to get as low to the ground as possible. Don't play their game and grind, just optimize for turn 3 kills and mulligan aggressively for them. Cut BBE and Bonecrushers, and board in veils and relevant hate.
-Versus typical aggro or burn, you can often outgrind them. Bring in the dragon's claws (if they're on red), the BBE, the EftW, and cut Mutagenic Growths and a few BTE/Bushwhackers. If Bomat is bad, cut it too.
-Versus combo, pretend to sideboard and run it back. Bring in veils, rav traps, or pithing needle if it's relevant, but the list is optimized to be as fast as possible for game 1, so it should work fine. If they get a turn 2 combo, cry.
Archetype Specific:
-Versus infect, remember that you didn't put Sudden Shock in your sideboard again and cry a bit. Hope to RNJesus that you draw multiple bolts and stomps, and bring in artifact/land hate for inkmoth nexus. Cut hammerhand and top end. Block glistener; bolt agent. This matchup is hard but winnable, probably.
-Versus dredge, bring in the rav traps and needle. Cut Bonecrushers or BBE. Name conflag with the needle. Use the rav traps only to negate creeping chills or get massive value if they dredge too greedily and stack some triggers. If they get lucky and make some amalgams on turn 2, you lose unless you can time an atarka's command well and blow them out. Bloodghast can't block.
-Versus amulet titan, bring in all of your artifact hate. Cut the BBE and Bonecrushers. Hope you draw better than them. They run even less interaction than we do, so as long as they don't turn 2 or hit multiple radiant fountains, it's doable. Try to win the dice roll.
-Versus Urza piles, bring in artifact hate. Rav traps aren't worth it. Cut top end and get as low as possible. Keep in the hammerhands, you can shatter the construct and make Urza unable to block to sneak by a lot of damage.
-Versus burn, bring in the dragon's claws. Pithing needle if you suspect a planeswalker or want to cut them off Sunbaked Canyon. Mulligan aggressively for the claws. Consider bringing in artifact hate to get rid of their claws. It's all about the claws. Using atarka's command as a Skullcrack is mostly a bait from what I can tell; you don't really want to hold up mana on their turn if you can help it (because you miss so much prowess value). Stomp gets around Kor Firewalker's protection; stomp in response to blocks to get some big boy value. Leave one or two mutagenics in if you can, because they can save your creatures from non-path removal. If they have a lot of path-effects, leave BBE in and let them ramp you. This matchup is very skill intensive, and takes a lot of practice to figure out all of the timings.
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Some handy numbers:
Mutagenic + Swiftspear = 4/5
Atarka's + Swiftspear = 3/4 (3 face, then 3 more for each prowess creature that hits)
Swiftspear + Burning-Tree + Bushwhacker = 7 damage
Swiftspear + Mutagenic + Bushwhacker = 7 damage (but never play this line please)
3x Prowess + Atarkas + Bolt + Mutagenic = 23 damage on turn 3
