Millicent, Restless Revenant
An Azorius spirit tribal deck from Innistrad: Crimson Vow, led by Millicent, Restless Revenant, generate flying spirit tokens whenever spirits deal damage or die, and build an aerial army that grows every combat.
The vampire wedding half of Innistrad. Two decks: Azorius Spirits and a Rakdos vampire deck built on Blood tokens.
A Blood token lets you pay one mana, tap it and discard a card to draw one. Cheap filtering that also counts as an artifact, which matters more than it first appears in a deck with sacrifice payoffs.
Pair a creature with another one as it enters, and both get an ability while they stay paired. Eight cards in the Commander decks use it, and it is a quiet way to hand out keywords without an Aura.
When an exploit creature enters you may sacrifice a creature, and if you do you get a payoff. It gives the Rakdos deck something to do with the tokens it keeps making.
A creature with training gets a +1/+1 counter when it attacks alongside a bigger creature. It rewards attacking as a group, which suits a token deck.
Crimson Vow is the second half of the Innistrad pair, set at a vampire wedding. The two Commander decks match the guest list: the Spirits haunting the place and the vampires hosting it.
Blood tokens are the mechanical contribution and they aged well. Discarding a card to draw one looks minor until you pair it with madness, graveyard payoffs or artifact counting, and the Rakdos deck touches all three.
Spirit Squadron is the more conventional of the two. Millicent makes a flying token every time another Spirit dies or enters, so the deck rebuilds itself through board wipes better than most token decks its speed.
Soulbond is the quiet mechanic in both boxes. Pairing a creature as it enters hands out an ability without spending a card on an Aura, and unlike an Aura it re-pairs when something dies. It is old technology, but in a precon it does a lot of work for very little text.
Neither deck is fast. Both want the game to reach turn seven or eight, and both have enough removal to get there. If your pod plays at a quicker pace, the vampire deck is the one that can keep up, since Blood tokens smooth its draws and the life loss adds up whether or not you are attacking.
Vampiric Bloodline is the more powerful of the two and the more fun to upgrade, since vampires have deep support. Spirit Squadron is the safer choice at a table with a lot of board wipes.
Millicent, Restless Revenant
An Azorius spirit tribal deck from Innistrad: Crimson Vow, led by Millicent, Restless Revenant, generate flying spirit tokens whenever spirits deal damage or die, and build an aerial army that grows every combat.
Strefan, Maurer Progenitor
A Rakdos vampire deck from Innistrad: Crimson Vow, led by Strefan, Maurer Progenitor, generate Blood tokens whenever opponents lose life, then sacrifice two Blood to deploy any vampire from your hand tapped and attacking with indestructible.