The only Destiny Knot in the game is located on Route 224, which lies to the east of Victory Road.
Reaching the Destiny Knot’s exact location requires the HMs for Waterfall, Rock Climb, Surf, and Strength (for the first visit only), and you can only get the Destiny Knot after you receive the National Pokédex.
Destiny Knot Location (Step-by-Step)
The Destiny Knot is on Route 224, which is accessible only through a cave that becomes unobstructed after you receive the National Pokédex.
The following Hidden Moves are required to reach the Destiny Knot’s location:
- Rock Climb
- Strength (first visit only)
It’s a long journey with lots of strong wild Pokémon, so you might want to make sure you’re stocked up on Full Restores, Escape Ropes, and Max Repels as well.
When you’re fully prepared, Fly to the Pokémon League to get started.
Use Surf at the lake and ride down the waterfall.
Step ashore to the south, then turn eastward to enter Victory Road.
Once inside, head southward down the wide corridor at the entrance.
Cross the bridge to the south and use Rock Climb to slide down the rocky wall.
Head to the west and turn north to pass under the bridge.
Make a left turn at the Veteran trainer, head up the stairs behind him, and cross the bridge heading towards the east.
Pass under the next bridge continuing towards the east and go through the newly-accessible entrance to the next cave chamber.
Note: If you haven’t yet received the National Pokédex, this cave will be closed off.
Once you’re in the cave, climb down the staircase and head northeast.
Descend the next staircase and head through the next doorway.
If this is your first time passing through this section of Victory Road, Marley will accompany you at this point and you will be unable to use Surf.
In this case, you will need to take the longer route to the north.
Otherwise, use Surf on the water to the east.
Surf northward and disembark at the square-shaped patch of land to the east.
Climb down the staircase here and head southward.
Circle around the rectangular lake and head north, passing the two Ace Trainers.
Wind your way through the linear path between the stones.
Head eastward and climb down the stairs you’ll find that lead towards the water.
Use Surf to go across the lake.
Step ashore and head down some stairs, and then Surf across yet another small lake.
Step back on land, head up the stairs to the north, and go all the way to the end here. Then take the exit to your right.
In this next area, head up the long staircase.
Leave Victory Road through the exit at the top.
Outside on Route 224, turn northward and descend the staircase.
Continue northward past the Ace Trainer.
Head all the way north until you reach the Veteran trainer, then take a right and travel east.
Keep going east as the fields turn into coastline.
Then eventually you’ll want to turn northward at the boulder at the corner of the beach, past the Black Belt trainer.
Keep going up, then take a left at the Ace Trainer NPC and head north up the staircase.
The stairs lead up to a terrace with an NPC, and in the northeastern corner you’ll see a Poké Ball item.
Pick up this item to obtain the Destiny Knot.
Note: This is the only Destiny Knot you can get in Pokémon Platinum.
Destiny Knot Details and Uses
The Destiny Knot is a held item with a unique effect:
If an opponent inflicts infatuation on a Pokémon holding it, the opponent will also become infatuated.
Infatuation is a status effect that makes half of all a Pokémon’s moves fail, so it’s a crushing status condition to have. But it’s also a rare condition to have.
Only two things cause infatuation:
- The move Attract
- And the Ability Cute Charm
You’re unlikely to come across many Pokémon that know Attract (which has around a 50% failure rate, since it only works on foes of the opposite gender), and the majority of Pokémon that have Cute Charm aren’t strong enough to worry about anyway.
So there isn’t much justification in taking up an item slot with a Destiny Knot unless you’re battling a very niche Pokémon team.
The Destiny Knot remains a mostly useless item until Generation VI and on, when it can assist with advanced Pokémon breeding techniques. But for Platinum it’s really not an item worth using.