Tholian vessel

A Tholian vessel was a type of starship employed by the Tholians during the mid-24th century.
When William T. Riker participated in a battle simulation at Starfleet Academy, he calculated a sensory blind spot on a Tholian vessel and hid within it. 
Many years later, in 2365, Lieutenant Commander Data noted this as one of Riker's various battle techniques while preparing for Operation Lovely Angel. ()
vessel