Mr. Miller, Economic Savant

Abilities of Mr. Miller, Economic Savant can only be activated during your upkeep
{1}{u}: Increase supply. (Each player draws a card)
{1}{r}: Decrease supply. (Each player discards a card)
{u}{u}: Increase demand. (Until your next turn, spells cost {1} more to cast.)
{r}{r}: Decrease demand. (Until your next turn, spells cost {1} less to cast.)