"WAH!" the Yoshi cries in pain as he gets stabbed! Though he manages to raise one arm and block one of the beaks with a Buzzy Bracer, though other manages to gouge him in the neck. Despite the dinosaur's soft and somewhat cartoonish appearance his body proves to be amazingly tough. The attack bloodies him, sure, but it doesn't punch nearly as deep as one might expect the wound to.
He quickly tucks into a tight ball and rockets upward, aiming to smash into the faces of the Brute with his shell and continue forward racing across the sand toward the three apparent non-combatants!
This should leave him safely out of the reach of the Manic, at least for now.
And now to another place with sand.
Once the spots fade from his vision the Glacial Dragon goes into a power dive! With one claw he'll attempt to thwack the flying kid out of the air and simply pile-drive him into the earth! And in the same motion try to smash the gunslinger with his tail.
The bullets bite into the monster! But at that range gravity takes quite a toll on their ability to cause much harm. Better wait for the monster to get closer. Like, say, on the ground thrashing people.