Simic Midrange
A Pioneer deck, by Ootani Yousuke
1st place at a tournament on 2019-12-01

Maindeck:

Creatures
4 Brazen Borrower
2 Elvish Mystic
4 Gilded Goose
4 Hydroid Krasis
2 Llanowar Elves
2 Tireless Tracker
4 Wicked Wolf

Instants
4 Once Upon a Time (Banned in Pioneer)

Legendary Artifacts
2 Heart of Kiran

Legendary Planeswalkers
4 Nissa, Who Shakes the World
4 Oko, Thief of Crowns

Basic Lands
7 Forest
1 Island

Lands
4 Botanical Sanctum
4 Breeding Pool
4 Mutavault
4 Yavimaya Coast

Sideboard:
2 Reclamation Sage
2 Scavenging Ooze
2 Voracious Hydra
3 Disdainful Stroke
2 Negate
2 Questing Beast
2 Entrancing Melody