Mighty Griptians are stronger than the standard Griptians. These creatures eventually replace all of the weaker variants later in the game, suggesting Mighty Griptians are Griptians that have matured and/or reached an advanced stage of their lives. They are slightly darker in color, and are more fearsome and dangerous; they have grown spikes along their backs (increasing the damage of their roll attack) and a set of wing-like protrusions from their shells. In some instances they can be seen hovering above the ground as they are rolling, but only for a short moment. These Griptians are summoned by MB in the Bioweapon Research Center, and Mighty Griptians also attack Samus during the post credits as she is nearing the Control Bridge.
Despite the fact that they are much stronger than the standard Griptians, they can still be defeated very quickly with a Super Missile or a Lethal Strike, provided they are knocked over by a Missile or Bomb first. However, they do not stay down for long; Samus must act quickly while they are fallen.
If Samus tries to Overblast a Mighty Griptian, they will always push her off, even if their health is low. If Samus fires a Super Missile at a rolling Mighty Griptian, it will knock them down instead of killing them.
"Griptians are armadillo type creaturs that attack by rolling into a ball and charging. They can burrow into the ground and appear under Samus to tackle her."