The last of the Three Trials, where the Guardian-to-be must overcome a seemingly-insurmountable obstacle to reach the Well of Making. For April, this barrier appears in the form of a deep canyon of mists, at the bottom of which Crow informs her is an endless abyss of nothing. It is uncertain whether the barrier appears as a chasm at all times or if this was simply the form April's Trial took.
April passes the Trial by persuading Crow to bring her a beakful of water from the Well of Making, and then to spit it out into the abyss, reasoning that something has to happen when water from the Well of Making hits absolute nothingness. The result is a bridge that spans the chasm, allowing her to pass.