Alk and Kiarah, Contagions

Deathtouch, menace
If a creature dealt damage by Alk and Kiarah, Contagions would die and did not have a plague counter on it, return it to the battlefield under
its owners control with a plague counter on it
instead.
As long as there is four or more plague counters
among creatures your opponents control Alk and Kiarah, Contagions has First strike