However when they finally reach the point at which they can seal the breach, the squad instead decides that they should kill the Firstborn rather than try to reseal the breach, as resealing would just result in them being trapped in the Box and endlessly tortured until the breach was opened again just like as happened with all their past allies. Traveling into the Firstborn's cavern, they find the creature in the middle of an island on a lake, with Leach bound to a nearby wall. Before Cole could identify the Firstborn's weaknesses, the Firstborn kills Cole and Jones and battles the surviving squad members.
When they reach a point where they can seal the breach, the squad chooses to kill the Firstborn instead of attempting to reseal it, as resealing would trap them in the Box and subject them to endless torture until the breach opens again, just like happened with all their previous allies.  Traveling into the Firstborn's cavern, they discover the creature on an island in a lake, with Leach bound to a nearby wall. Before Cole could identify the Firstborn's weaknesses, the Firstborn kills Cole and Jones and battles the remaining squad members.