The key card is present but its support is thin.
Prioritize useful support such as Galactic Wayfarer or Kav Landseeker.
With Tannuk present, make a normal land play and activate a Lander. The second landfall resolution draws a card; Crasher receives another attack boost.
Your deck already enables the plan but is losing the early turns.
Take a castable early creature or efficient answer before a second expensive payoff.
Landers cost two mana to activate. Ragost is a white splash, not an automatically castable red-green payoff.
The support is missing
Favor independently useful creatures and interaction if the narrow support does not arrive.