I've been wanting to build a deck around Young Pyromancer and Risen Reef for some time. For those unaware of the interaction, Risen Reef triggers for any Elemental and Young Pyromancer generates Elemental tokens. The effect is a pseudo-Skullclamp that "draws" one card but does not require mana and allows you to keep the creature in play, quickly building towards a lethal army. Oh, and it stacks, which gets pretty crazy. Additionally, Risen Reef cantrips and pitches to Force of Will, making it much less of a dead draw without Young Pyromancer compared to Skullclamp. The deck below is my first attempt at building around this interaction.
And it started off well. I had a lot of fun playing the deck on stream, put up a decent 7-3 record, and posted it to my twitter. User abr took the list and won a trophy soon after. It's well positioned against BUG and many other Blue control decks because of the "go-wide" strategy of Young Pyromancer and the value engine of Risen Reef that bypasses Leovold and Narset. It likely doesn't have a great matchup against Dredge and Shops give the speed of those decks and the lack of great tools for those matchups, but there aren't a ton of those decks in leagues (leagues are more similar to an FNM) and sometimes you get lucky.
Other Spells (12)
Explanation of Card Choices
Chandra, Acolyte of Flame - This card is very good in this deck. You want some sort of a Snapcaster or JVP effect to recast Time Walk and one shot your opponent with Elemental tokens. Chandra has the added benefit of creating more Elementals when Risen Reef is in play and drawing 2-4 cards per activation. She can also pick off Narsets and Teferis if needed. Chandra is a unique combination of attributes of both Snapcaster Mage and JVP. I think she should see more play but the double red has certainly limited the shells in which that is possible, while the three drop Walkers have provided a lot of competition.
I honestly am not a huge fan of Spell Pierce in this metagame and generally prefer Daze and Force of Negation in that slot. The problem is that the format is very tempo-based and holding up Spell Pierce often means delaying your own game plan on the chance that the opponent plays a spell worth Spell Piercing. And you can easily get burned when that spell is a Leovold instead of a Narset or Deathrite Shaman instead of a Preordain. Daze and Force of Negation don't require holding up mana while Pyroblast still has removal properties (you can hit a Leovold after it resolves though it is certainly worse to do so). That's in addition to the huge difference in play/draw utility of the card.
Veil of Summer - I think most of the other maindeck inclusions are pretty reasonable. Veil of the Summer might seem odd, but in the context of BUG being 50% of recent top 8's I think it makes a lot of sense. Veil of Summer is one of the few counterspells for Abrupt Decay AND IT DRAWS A CARD. It's not as good as a proactive counter but since Young Pyromancer is one of the key cards for beating BUG, protecting it is paramount and Veil of Summer is the best card at doing that.
Sideboard - I really wish I had more Dredge and Shops hate. As it is, Ravenous Trap is probably the best Tormod Crypt effect and I like Cage over Leyline since I can't always protect or cast Leyline and don't have the Wastelands and DRS for incidental hate. Ideally I can protect or resolve Cage with Missteps, Pyroblast, Veil, etc. and contain Hollow Ones with the Pyromancers. Against Shops, I lack the Green count to effectively run Force of Vigor, so the best removal spell available to me is Shattering Spree. Collector Ouphe is the best Rod effect. If I had more slots, something like Mindbreak Trap or Force of Negation would be valuable as a way to protect from turn 1 brokenness since I can't play Force of Vigor.