Zero-Coupon Bond

suspend 4-{x}{1}{g}
When this card has 0 suspend counters on it
add X+X to your mana pool.
If this card has been suspended before, suspend
it again with 1 less suspend counter. After this
card has no suspend counters and cannot be suspended again it loses all abilities and gains:
"{t}: add X +2 to your mana pool"