Using the Stasis Exotic heavy GL can boop wizard toward you if you keep plopping a crystal wall behind it and then blow it up to move him off the cliff, this is a method if you are very bored or if you accidentally pushed him too far away with a rocket-pistol. Alternatively, grabbing a Knight's sword, sprinting and jumping off the pointy rock and doing a light attack can launch you at wizard while also breaking shields, after you have done this and have retouched the ground finish wizard with whatever you got be it rocket or grenade or rocket-pistol.