As I remember, in the old version of Binding of Isaac using items like Book Of Shadows, My Little Unicorn, or The Gamekid when passing over the spikes will render the player invulnerable to the spikes and quickly spawn the chest.
Does this "trick" still work in Rebirth?
Best Answer
You must actually take damage to get loot from a Sacrifice room. You can walk on spikes as much as you want when you're invulnerable, but you won't get anything from it.