Enlarged monsters (and occasionally brainwashed Zords) often destroy buildings and cause earthquakes that open ravines.
Lord Zedd enlarges monsters by detonating bombs on them, and a fiery explosion is seen before they are enlarged.
Lord Zedd's Putty Patrollers break into pieces of clay when defeated. Although this is not especially graphic, the stop motion animators were forbidden from ripping the Putties' heads off.
Monsters are destroyed in non-gory explosions [some of the monsters are turned back into the items they were created from in the first place].