Omnath leads a tribe of elementals whose enter-the-battlefield triggers pile up value while your mana stays banked.
Sets your commander and theme, then adds about 25 cards that fit plus 20 lands. You fill in the rest.
The top 40 of 231 cards that fit

#1,659$3.46Scott M. Fischer

#3,924$0.31Zara Alfonso

#5,213$0.23Jehan Choo

#6,580$0.13Jonas De Ro

UnrankedCristi Balanescu

#20,516$0.14Chippy

#1,019$27.95Filip Burburan

#3,520$0.34Diego Gisbert

#4,077$0.74Heonhwa

#2,774$13.58Tuan Duong Chu

#1,128$26.15Allen Douglas

#2,847$0.89Kisung Koh

#295$0.43Aleksi Briclot

#3,615$0.65Simon Dominic

#5,725$0.24Raymond Swanland

#6,802$3.79Wayne Reynolds

#5,792$0.18Filip Burburan

#9,576$4.55Jae Lee

#1,862$0.25Ryan Yee

#4,932$2.95Terese Nielsen

#17,101$6.03Raymond Swanland

#2,784$6.01Jehan Choo

#12,869$0.16Even Amundsen

#2,088$21.44Tuan Duong Chu

#693$12.02Grzegorz Rutkowski

#3,603$4.68Brandon Kitkouski

#6,851$0.20

#14,716$0.32Jeff Miracola

#13,233$0.21Lars Grant-West

#5,223$3.63Kekai Kotaki

#10,932$0.38Michal Ivan

#11,798$25.84Grzegorz Rutkowski

#10,360$0.28Chippy

#8,393$0.38Tyler Jacobson

#3,790$0.15Cristi Balanescu

#2,554$0.31Lucas Staniec

#3,745$0.20Eric Deschamps

#1,338$3.11Anastasia Ovchinnikova

#23,284$3.49Gustavo Pelissari

#6,135$0.24