When a card with Escape is in your graveyard, you may cast it by paying its escape cost, which is both the mana cost written and exiling the cards
Its less about rushing the board and more about slowly taking control of the match until victory is inevitable
4BB, T: Put target creature card exiled with The Darkness Crystal onto the battlefield tapped under your control with two additional +1/+1 counters on it
You need to pair it with some library manipulation to reliably use it as a ramp card and unless you are playing a turn one Brainstorm, Ponder or at a stretch Serum Visions you are not going to be able to use it as ramp on turn two when you most want it
Sacrifice Golgari contains plenty of sacrifice outlets like Grist, the Hunger Tide and cards that produce sacrifice fodder like Compy Swarm and Creakwood Liege
In fact, I wouldn't consider picking up power or any older cards worth more than $200 without a thorough knowledge on what to look for