Twins of Destiny

Lifelink, First Strike
{w},{t}: Gain 3 life. Place {e} on Twins of Destiny.
{b}{e},{t}: Each player loses 2 life.
When Twins of Destiny has {e}{e}{e}, sacrifice it
to draw seven cards and gain 7 life.
One daughter of dusk, the other of dawn. But
which will save us?