The Maverick Malcontent

Pay an additional {w}, {u}, and/or {r}.
{w}: Creatures you control get +X/+X until the end of turn, equal to the number of plains you control.
{u}: Look at the top cards of your library equal to the number of islands you control. You may put those back at the top of your library in any order.
{r}: Draw cards equal to the number of mountains you control, then discard 3.