Ather spring

at the beginning of your upkeep pay {5} or
sacrifice Ather spring
{c}{c}{c}{c}{c}{t}the next spell
you cast you don't have to pay its mana cost,
sacrifice Ather spring
{t}add {c}{c}{c} to your mana pool,
{c}{c}{c}{c}{c}{c}{c}{t} add {w}{u}{b}{r}{g} to your
mana pool
{10}{t}cast any card from your library without
paying its mana cost,sacrifice Ather spring