A strategy that dates back to early Magic and Counter-Slivers, to present a fast clock backed by agile counters and interaction, has always been a player favorite. Faeries was a prime example of this, but Spirits might be the future of the strategy.
Noble Hierarch isn’t a Spirit, but it’s nearly alone in that here. The Hierarch does, however, fix your mana, give you the ability to ramp, and even increase your clock or make sure your solo attacker is bigger than opposing blockers. This is one of the best cards in all of Modern, so if you’re going to play a green creature-based strategy, especially in the Bant colors, you should strongly consider playing 4.
Mausoleum Wanderer starts off the disruption package with a cheap creature that can get in for meaningful damage. With so many combo decks in Modern, as well as a plethora of decks that rely on tempo, the mere threat of the Wanderer countering a spell can really throw a wrench in the opposing game plan. The Wanderer can grow for extra damage, and your instant-speed Spirits add another layer of annoyance as both combat tricks and to throw a wrench in their plans to play around its activated ability.
Rattlechains makes opposing removal look silly. You’re getting a 2-power flying threat for just 2 mana, so you can play it at instant speed for no additional value and still feel good about your card. But when you do get value, it tends to be ridiculous, countering key cards like Path to Exile, Lightning Bolt, and the otherwise uncounterable Abrupt Decay. Giving your future Spirits flash means that you’ll no longer be tapping mana on your turn and you’ll always have options, making any opponent’s day miserable.
Selfless Spirit is a well-costed aggressive creature, but the protection of saving a creature from a spot removal spell while also saving your team from one of Modern’s many sweepers makes it excellent in a deck playing nearly 30 creatures.
Drogskol Captain pumps your entire team while also protecting key Spirits from spot removal. The weakness of so many creature decks is that opposing Jund players have Bolts, Fatal Pushes, Maelstrom Pulses, etc. to keep their life totals high. Those are ineffective spells against hexproof, and a pair of Captains in play will make sure nothing is targeted any time soon.
Spell Queller is an insane tempo spell and the Spirit you will likely most want to protect with all of your Selfless Spirits and hexproof enablers. Countering a key spell messes up every deck in Modern, and you get to start attacking afterward. With so many instants and flash spells in the deck, Spell Queller is nearly impossible to play around.
Geist of Saint Traft will just destroy any deck that’s looking to interact with spot removal and can’t do a great job sweeping the board or blocking. With other cards in the deck to pump your Geist, blocking isn’t always a guarantee, and Selfless Spirit can also make combat a nightmare.
Phantasmal Image isn’t at its best here, what with Spell Queller needing to be cast at instant speed and Geist being legendary. Copying a Captain, however, is insane, and both your Captain and image will now have hexproof (nullifying its drawback).
Collected Company is the real reason you’re splashing green. Every card in this deck is a hit, and so many of them are incredible at instant speed. Casting a removal spell against 4 open mana in this deck could already mean any number of terrible things for your opponent, but now a Company can simply hit a Captain or Rattlechains to give hexproof, Selfless Spirit to save it, Spell Queller to exile the spell, Wanderer to counter the spell, etc.
Path to Exile is just good removal, although it doesn’t play so well if you need to rely on Wanderer to counter something, so keep that in mind.
The final card is a single Steel of the Godhead. This will speed up your clock and make it much easier to race when put on a Captain or Queller, but the real gem is on a Geist of Saint Traft. A 4/4 unblockable, hexproof, lifelink creature that makes 4/4 attacking flying Angels is rough!