Lego Lord of the Rings -
Gollum will be constantly moving along the opposite wall - to make him come down, you need to throw a fish at him. One is lying right in front of you - pick it up and throw at the enemy. When Gollum gets down onto the ground, switch to Sam and throw his rope at him. That will make Gollum angry and he will attack the Hobbit; in order to damage him, switch to Frodo and attack with his sword. Gollum will head back onto the wall and you don't have any fish left to make him come down.