The Payback vs The Scourge

Now that the good ship Payback (Formerly the Drudge, renamed by Camella Ann) is behind the enemy lines of the Scourge, you are able to make it to the Dark Spiral Rift (almost like a Black Hole in space without all that crushing effect in the center) that the enemy is using to invade.

You realize that very few enemy ships are coming through. Based on previous battle reports, from the outer rim worlds, you estimate the full invasion force has already passed through. Therefore closing the Rift will be useless to save your worlds.

The Arcanists (Cristalla, Arcamedies, Chiana and Camella Ann) study the Necronomicon Tome and discover that there is a ritual that can be cast that would summon the Scourge of Nyarlathotep to a fixed point near the ritual. As a group you feel that's a great idea, until you realize you would be surrounded by the enemy on the wrong side of the Rift.

Searching for an alternative, you find another helpful ritual. It's called Recursion. It's unsure on how it specifically does it, but it would definitly eradicate the Scourge once and for all.

The Summoning Ritual will require two trained Arcane Casters, Casting time: 5 minutes
The Recursion Ritual will require four trained Arcane Casters, Casting time 2 minutes, however each caster can take a one round break from the casting every other round. This spell can only affect the creatures that are present at the start of the Ritual. This ritual cannot be cast on the Prime Material Plane.

Oh Oh, what if we don't have enough casters, can we use some of the "other" crew members?

You have enough casters. If you aren't there your PC will be used as an NPC.