SlayerFusion
the Fusion of multiple Slayers (the definition of Slayer is dependent on the the reference being used). Often into one entity. (though if death is involved also depends on the reference)
(Person 1) got splattered by (Person 3)
(Person 2) got splattered by (Person 3)
(Person 3) made a SlayerFusion out of (Person 1) and (Person 2)
(Person 2) got splattered by (Person 3)
(Person 3) made a SlayerFusion out of (Person 1) and (Person 2)