Every fight and every turn adds counters, so the Tarrasque outgrows anything that stands in its way.
Sets your commander and theme, then adds about 25 cards that fit plus 20 lands. You fill in the rest.
The top 40 of 815 cards that fit

#15,584$0.95Yongjae Choi

#1,582$34.03

#7,889$0.35Jaime Jones

#17,677$0.11

#1,127$5.77Chris Rahn

#7,383$0.25

#2,515$6.16Kevin Sidharta

#2,733$0.29Aaron J. Riley

#7,125$8.75

#7,463$5.99Heonhwa

#6,382$0.33

#10,930$0.59Karl Kopinski

#5,237$1.90Raymond Swanland

#7,927$0.13Volkan Baǵa

#22,436$0.09Tyler Jacobson

#6,580$0.13

#5,082$0.35Izzy

#13,150$0.24James Ryman

#7,532$0.38

#4,956$2.29Jason Kiantoro

#3,139$4.43

#3,846$0.27Daarken

#14,716$0.32Jeff Miracola

#1,659$3.46Scott M. Fischer

#1,628$3.22Chase Stone

#7,762$15.05Billy Christian

#14,962$0.33Howard Lyon

#9,461$0.30Zack Stella

#10,317$0.38Steve Prescott

#7,795$0.28Daarken

#917$25.23Dan Hipp

#17,979$0.05Clint Cearley

#1,591$16.75Lucas Graciano

#16,545$14.25

#425$5.55Daniel Ljunggren

#227$63.96

#1,015$0.69Lucas Graciano

#8,934$0.32Andrey Kuzinskiy

#7,276$0.40Josiah "Jo" Cameron

#2,472$16.85