At the beginning of your end step, if you sacrificed three or more Clues this turn, transform Havengul Laboratory.
(=SLD 609)
Reverse Type:
Legendary Land
When this land transforms into Havengul Mystery, return target creature card from your graveyard to the battlefield.
When the creature put onto the battlefield with Havengul Mystery leaves the battlefield, transform Havengul Mystery.
{T}, Pay 1 life: Add {B}.