Shrine of the Fallen

Exclude (before the game begins reveal this card
to all players and you may chose to exclude
one color from this cards color identity)
Whenever a creature you control deals combat
damage to a player or planeswalker add that
much {g}, if green is excluded from this cards
color identity add that much {c} instead. Until
end of turn, you don't lose this mana as steps and
phases end. Then create a 1/1 colorless spirit
creature token with flying.