Chaos Moon

At the beginning of each upkeep,
count the number of permanents. If
the number is odd, until end of turn,
red creatures get +1/+1 and whenever
a player taps a Mountain for mana, that
player adds an additional Red. If the number
is even, until end of turn, red creatures
get -1/-1 and if a player taps a Mountain
for mana, that Mountain produces colorless
mana instead of any other type.