Suspend opponent digimon then piercing. That's it, that's the main strategy of this deck.
For grandiskuwagamon you can use Okuwagamon(X antibody) since it can reduced cost by 1 making it 3 or normal with grankuwagamon by 1 cost i recommeded using X Antibody so that you can activate Grankuwagamon Second effect and GrandisKuwagamon effect