The goal is to get big fast and crush them underfoot. Use Tyrannomon X, DarkTyrannomon X, and Ryutaro to hit level 6 quickly and obstruct the board. MetalTyrannomon is strictly the better choice for level 5, as he blocks the common ways to remove Dinomon that do not interact with Fortitude. Slide X Antibody under Dinomon after Fortitude for another free Fortitude use. Alexandrite Memory Boost isn't out yet, use Garnet instead.
