Edison Format · March 2010
The effect of "Skreech" activates at the end of Damage Step, when monsters destroyed by battle are sent to the GY, but "Skreech" does not have to be 'sent to the GY'. The effect of "Skreech" activates in its owner's GY (or Removed Zone, etc.)
If you take control of your opponent's "Skreech", and it is destroyed as a result of battle, then your opponent (the original owner) will activate its effect.