Paozo

Paozo (パオゾー) is an elephant robot that throws his ball after the player, both of which he then sucks back to him to throw it back again. There are two varieties: one has a red ball that travels straight away from it, another has a green ball that bounces around to the opposite side of the screen. There are three of them in total, each found consecutively in Concrete Man's stage and must be defeated to proceed. They are also present in the Special Stage. Given its huge size, it's particularly vulnerable to a fully charged Magma Bazooka shot at medium range. The Plug Ball also works well.

Strategy
There are three Paozos in Concrete Man's stage. They all have balls in front of them, then they'll roll or throw them toward Mega Man with their trunks, then suck the ball back, then so on.

The first one is really simple. He has a red ball and collar, so the ball will roll. There is a ladder right above the ground, and Mega Man can easily blast the elephant as long as he hangs on to that ladder. The second one has a green ball and collar, so he will try to flip the ball upwards. Stay near the elephant then start firing. The last elephant also has red gear, however, there is no ladder and there are holes in the ground. So if Mega Man gets hit with the ball when the elephant pulls it back, he will probably fall to his doom right before the checkpoint.

Mega Man (Archie Comics)
A Paozo has a cameo appearance in Sonic Universe #53, where it carries Orbot and Cubot around.