Groundshaker

Groundshaker is a boss from Kingdom Hearts II.

Groundshaker is a mega doppelganger-like Living Bone who roams the Pride Lands after Simba triumphs over Scar's Ghosts. The ghosts all merge to form the gigantic Heartless that is easily one of the biggest Heartless Sora ever fights, comparable only to the World of Chaos. The top of the beast is very much like a lush Savannah. He is the boss of the Pride Lands on the return visit.

Atop the beast is an unnamed witch doctor Heartless who resembles a Shaman. Similar to the Shaman and the Living Bone, the witch doctor forms a symbiotic relationship with Groundshaker. When the witch doctor's double-mask rotates, Groundshaker's head would also rotate. One side uses volcanic fire attacks, while the other side uses eerie electric magic.

It is unknown whether the beast or the witch doctor is the Heartless named Groundshaker. Timon hints that the witch controls the beast. It is entirely possible that they are one in the same, as the witch doctor sometimes merges with the beast. However when it dies the Shaman is the only one seen to vanish and a heart pop out. It is easy to tell what earlier Heartless inspired Groundshaker--he has uncanny resemblance in attack style to Behemoth from Kingdom Hearts.

Kingdom Hearts II
''A giant Heartless that appeared in the Pride Lands. He was created by the many illusions of Scar.''

The main body on the back of the creature controlled its bones, creating chaos in the savannah.

Strategy
The main thing to remember is that the only available targets are its eyes and the shaman-like Heartless on its back. At the start of the battle a series of reaction commands become avaliable helping Sora jump from the AoE ground stomps from its feet. The computer controlls your movements, so you don't get confused. With the last reaction command you will eventually jump up and parray one of its stomps by pressing rapidly, when you do this it will fall and become stunned. Now is your chance to unload the most damage you can to its main head's eyes. Magic, meele, Simba's limit, anything that deals damage.

When the Groundshaker recovers you can jump on its back using the reaction command "jump" twice. Theres a shaman monkey-like Heartless here that is the hardest part of the fight. At high health you can attack any of the two heads to take off HP while it casts mild magic that you don't have to worry about if your within meele range. A tip for taking this down, while attacking in the air, press to perform Finishing Blast, this will knock its two heads off on the ground for a short period, Happy Nuking. If it runs away then repeat the process from the beginning to get back on its back.

When it is upright again on the Groundshaker's back the Shaman can go invisible and use Fire-like or Thunder-like attacks. During this time it is adviseable you run clockwise around the boss' back until it's visible again, then try and stun it with the air combo just mentioned. The duration of invisibility and the intensity of magic attacks becomes more frequent as its HP drops lower. As with all boss battles heal well, for this boss never lets your HP go down to less than about half of the first circle around Sora's portrait, it can kill you with 1 shot if your health is any lower than that in Proud Mode.

When you fall off the back jump up the leg or the head to get back on. Don't stay on the ground when the Shaman is on it's back. You will get bombarded by magic attacks and make it almost impossible to survive, let alone get back up.

Trivia

 * It is believed that Groundshaker is the largest Heartless that Sora ever fought (excluding World of Chaos).
 * Based on the beta screen shots, many fans believed that Behemoth would appear in Kingdom Hearts II. It did, only in the Battle of 1000 Heartless, but it could not be fought. Instead, Groundshaker took Behemoth's place as a boss battle.
 * The Groundshaker seems to have been inspired by some of the costumes in the Broadway version of the Lion King.