Rockhenge, Heart of the Trolls

{t}: add 2 mana of the color of your choice. This
mana may only be used to cast Geomancy or
Troll spells.
{t}: add {1} to your manapool
Sacrifice Rockhenge: return all Geomancy or
Trolls spell in your graveyard into your library,
then reshuffle your library.