With Standard’s bannings, the losers are clear. U/G-based energy decks, namely Temur, and red decks took a hit. They’re both still standing, and they’re reasonable options going forward, but some of the most powerful cards in the format that were pushed aside gained some value. B/G is absolutely back on the map with these bannings and some new Rivals cards.
Winding Constrictor is inherently powerful. A 2/3 creature for 2 used to cost double-colored mana and have 0 abilities. Elvish Warrior was once above the curve, and Winding Constrictor really puts that to shame. Attune with Aether being banned is a bit unfortunate for the Snake as combining with Longtusk Cub was a great way to put an opponent away on turn 3, but there are still excellent options. Constrictor still boosts your energy, but with so many cards that utilize +1/+1 counters, the Snake is sure to rise up as one of the most important cards in the format once again.
Walking Ballista is one of the best combos with Winding Constrictor, and if red decks are going to go more aggressive with 1-toughness creatures (not to mention Merfolk and Vampire tribal decks if they ever get off the ground), then Walking Ballista can dominate the format. Getting an extra counter when you cast Ballista is already excellent, but being able to spend 4 mana to put multiple counters on it in the middle-to-late stages of the game gives you a great mana sink.
Merfolk Branchwalker already saw some play in W/G Aggro decks and has begun to make a splash in Modern U/G Merfolk. Branchwalker also combines well with Winding Constrictor as you’re either getting a 2/1 creature that draws a card for 2, or you could be getting a 4/3 that gives you an effective scry 1. Setting up your draws while still having a creature with an excellent floor means that the Branchwalker is sure to have an impact on Standard going forward.
If Branchwalker is good, then there is no adjective strong enough to describe Jadelight Ranger. This card is obscene, and curving Constrictor into Jadelight is disgusting. For just 3 mana, you’re getting a 2/1 creature with two explores. This means that if you curve Snake into Ranger and hit a spell on top, you have the option of leaving it there even if you want it in the graveyard just to lock your Ranger in as a 6/5 on turn 3. The “floor,” if you can call it that, is a 2/1 that drew you 2 cards and cleared 2 lands off the top of your deck. There are times when that won’t be good enough, but this card is insanity.
Rishkar, Peema Renegade is still a great combo with Constrictor and all the other creatures with counters. Most cards in this deck are capable of granting some +1/+1 counters, and Rishkar will either accelerate out a bigger threat or just put more counters on Ballista later are all great. Snake into Rishkar turn 3 means that you have a pair of 4-power creatures on the battlefield… that’s tough to ever beat.
Verdurous Gearhulk is your endgame. With a Snake in play, you’re looking at potentially distributing eight +1/+1 counters among four different creatures. Oh, and you still get that 4/4 trampler out of the deal. Putting counters on Ballista to machine-gun them down is a pretty effective way to end the game.
Your creatures that don’t combo with Constrictor are Ripjaw Raptor and Ravenous Chupacabra. These 4-drops may not synergize with the counters, but they offer some serious card advantage, killing a creature no-questions-asked or putting a 4/5 into play that starts drawing cards if anyone messes with it. Getting a Raptor out when you have a Ballista with extra counters is a sick card drawing engine that can bury the opponent.
Your spells help fill the holes. You have Fatal Push as a solid removal spell that gets back some tempo, and there’s Vraska’s Contempt to deal with indestructible and/or haste creatures, and take care of problematic planeswalkers. Blossoming Defense can help win a combat or, more likely, counter a removal spell from the opponent for just 1 mana.