Olympus Realm of the Gods Walkthrough
You will immediately have to deal with a fight against a horde of bull-looking Heartless. These enemies pack a punch and have heavy armor. Try to survive for as long as you can and then Goofy will unlock the Trinity Guard ability for you. Use it and ram into the bulls headfirst to destroy their armor. Make sure to use the finishing move and it will take out their armor, letting you finish them off easily.
Go to the right and you will find a chest. Go to the opposite side of this large room and you will find another chest against the wall. Then go through the doorway at the very back of this room. Go up the stairs and another staircase will be in front of you. Go under the stairs to find a chest. Then go up the stairs and you will have a fight against a sandworm and normal Heartless.
This is a great time to practice your new Shotlock ability. Hold down RB/R1 to target the enemies and then unleash the attack. Finish these enemies and then continue into the next area called the Corridors. Grab the map in the chest next to the save point and go up the stairs to the right and then take the stairs to your right again. There will be a chest here on your left.
Then go back down to where you entered the Corridors area and go left this time. You will find another fight against Heartless and a sandworm. Use shotlock and abilities to take them out. Then continue your way into the portal for an on-rails optional minigame. Hold down the right trigger to fire a burst of energy at enemies and jump to avoid attacks.
When you get to the end of the rail, go to the right to find a chest. Then go left and up the stairs to encounter some Heartless. Continue up the stairs and you will be able to dive off. Dive and land back in the Corridors. Head right and then left and up some stairs to come to a platform and a purple circle in front of it.
What you are going to want to do is go up the stairs to the platform and hold down RB/R1 to go into Shotlock mode. From there, quickly look up for a glowing square on one of the floating debris and press X/Square to airstep to it. Continue airstepping up the debris until you reach the top. Before you go any further, turn around and dive below. There is a building about halfway up with what looks to be a large red wrapped gift. Dive attack it and it will reveal a chest.
Go back up to the Apex and walk toward the gates to initiate a cutscene and the final boss fight for Olympus.