How do Sliver Overlord and Mirror Entity react together?
Mirror Entity does not allow Sliver Overlord to find any creature

"Creatures you control" always refers only to the Battlefield, never to cards in any other zone (those will be referred to as "Creature Cards").

Mirror Entity interacts with Sliver Overlord in the following ways:


Sliver Overlord can search for or gain control of Mirror Entity
Mirror Entity can change the creature type of Sliver Overlord (and all other creatures (on the battlefield) you control) to all types.


There are no other interactions between these two cards.