While Pokémon BDSP isn't based on the fourth-gen Platinum Edition, Studio ILCA has hidden a major Easter egg in honor of the 2008 expansion Diamond Pearl. Not only can trainers find Giratina in secret locations hidden on the map, but they can also transform legendary Pokémon into their epic original form after unlocking the Griseous Orb in Pokemon Brilliant Diamond Shining Pearl.

Where to find Giratina in Pokemon BDSP

While the extended platinum ending isn't in Pokemon Brilliant Diamond Shining Pearl, Studio ILCA gives trainers the chance to capture the legendary Giratina.
Players will first be able to find the Creation Trio Ghost-type after clearing the level. Here are the steps required to find Giratina in BDSP:

You must first the Elite Four and Cynthia to become the new Sinnoh Champion. After this, you need to complete Sinnoh Agility by looking at all 150 Pokemon.
Head to the town of Sandgem and Professor Rowan will provide you with a national picture book.
Now that you have National Dex, return to Veilstone City and take the South Exit onto Route 214. Follow the path on the right until you reach the middle.
You will see an opening and the trees form a secret passage. Take it into the path of spring. This will eventually lead you to an entrance that turns into a clearing on the side of the hill.
Climb the mountain with the Rock Climb HM. You will now be standing on top of a hill overlooking the lake. Turn right on the basket and head to the north side.
Use Rock Climb again to minify. You should end directly before the cave entrance.
You have now found Turnback Cave, Giratina's lair.

How to capture Giratina in BDSP

Now that you've found the turning hole, you'll need to do a little extra work to meet the mysterious legend.

Once inside the turnback hole, use a defogging HM to clear the air so you can see.
The trainer now needs to find three pillars. In each room, go through the North, West, or East exit.
Every time you enter a new section, look for a pillar in the center of the room and touch it. You will know if you found a new one because it will have a new sequence of numbers.
Once you find the last pillar, continue on the north exit until you enter a room where you can see the legendary Giratina sitting in the middle. Make sure to save your game.
Walk up to the ghost type and interact with it to trigger the battle. You can now catch 'mon in this encounter.

Where to find Griseous Orb

Studio ILCA has not only added Platinum Legends to the Sinnoh Remake but has also created a hidden method for players to obtain Ash Orbs, turning Giratina into its original form. Players will only be able to unlock key items after gaining the post-match Ramanas Park feature and fighting Giratina for the second time in a secret boss fight.

After obtaining the National Pokédex, you need to catch Giratina in the Turnback Cave.
Now head to the town of Sandgem. Walk south to the shore of the beach and use the Surf HM to enter the waters of Route 219. Continue east, crossing Route 220 and 221.
You will eventually reach land. Take the road that leads to La Ramanas Park. Enter the building and speak to the receptionist in the lobby to enter the store.
You should see Twisted Tablets selling 1 Mystic Shard (L) or 3 Mystic Shards.
To get Mystery Fragments, use your Explorer's Kit to enter the Great Underground. Look for golden glitters on the radar, then use your pickaxe to mine walls that have a random chance to drop them.
If you can't find anything, go into a hideout, then exit to reset the wall generation and try again. This currency is very rare and may take some time to find.
Go back to the Ramanas Park lobby and buy the Twisted Slate. Now head to the Twisted Chamber Cave located in the northern part of the park and insert key items into the pedestal of the room for a secret boss battle with Giratina's origin form.
You can't catch Giratina a second time here, so you'll need to beat the level 100 version of the Legendary. After knocking it down, you'll get an Ash Orb as a reward.

How to turn Giratina into its original form

After fighting Giratina at Ramanas Park to get the Ash Orb, you need to add the Legendary Orb to one of your team slots.
Add Giratina to your party. Press the X button to pull up the menu and select the Pokemon tab.
Click on Giratina, then go to "Hold Items" and select Gift Items. This will take you to other item pockets.
Find Griseous Orb and click Give to a Pokemon. Then select the legend and it will now automatically transform into its original form.
To revert it back to its alien shape, just repeat the above steps, but this time remove the held item.

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