"Sinnoh" sounds similar to the Spanish word "cinco".
"Cinco" has five letters.
"Five" rhymes with "Overdrive".
Five is also the generation in which Reshiram and Zekrom were introduced.
Overdrive is a Plate in Pokémon Duel which targets Reshiram or Zekrom.
Coincidence? I think not! But what does it mean?
When affected by Overdrive, Reshiram's and Zekrom's damage is increased by thirty.
In dialects that use flap consonants, "thirty" rhymes with "birdie".
A birdie is a term in golf for a score of one under par.
"Under par" sounds suspicious… Could it be short for "under Parfum Palace"?
Parfum Palace has no accessible basement. However, on the map of Kalos it's shown to be rather near the Lumiose Badlands and, by extension, the Kalos Power Plant. Much of the plant's structure is underground. So the clue, "under Parfum Palace", must mean there's a secret underground tunnel connecting the two locations.
But what can we expect to find there?
The answer comes from a clue we noticed earlier—golf. Kahili is a golfer and a member of the Alola Elite Four.
Four is the number of colors represented by the Gen I core series games' titles.
Ditto was introduced in Gen I.
Ditto can transform into any Pokémon, including Kecleon.
Kecleon can change its color to camouflage itself, requiring a Devon Scope to see it.
"Devon" rhymes with "Route 37", which is a location in Johto near Ecruteak City, home of the Burned Tower.
Suicune can be caught at the Burned Tower in HGSS if it's defeated during its initial encounter.
So this means that Suicune is the one hiding in the Parfum–Power Plant tunnel! But why? To find out, we'll need to dig deeper.
Suicune's Hidden Ability is Inner Focus, which makes it immune to flinching.
In Super Smash Bros. for Nintendo 3DS, Giga Bowser is also immune to flinching.
Bowser's Giga Bowser transformation debuted in Super Smash Bros. Melee, even though Bowser himself is part of the Mario series.
For Western audiences, Marth also debuted in Super Smash Bros. Melee.
"Marth" rhymes with "Darth".
Did you ever hear the tragedy of Darth Plagueis the wise? I thought not. It’s not a story the Jedi would tell you. It’s a Sith legend. Darth Plagueis was a Dark Lord of the Sith, so powerful and so wise he could use the Force to influence the midi-chlorians to create life… He had such a knowledge of the dark side that he could even keep the ones he cared about from dying. The dark side of the Force is a pathway to many abilities some consider to be unnatural. He became so powerful… the only thing he was afraid of was losing his power, which eventually, of course, he did. Unfortunately, he taught his apprentice everything he knew, then his apprentice killed him in his sleep. Ironic. He could save others from death, but not himself.
"Himself" rhymes with "Azelf", a Pokémon from Sinnoh.
SINNOH CONFIRMED!