Kingdom Valley is an Action Stage in Sonic the Hedgehog (2006). It is north-east of Soleanna and once housed its old kings. The last resident of this place was the Duke of Soleanna but following the events of the Solaris Project, Kingdom Valley was largely abandoned. In the present, it is the site of one of Dr. Eggman's bases. Kingdom Valley abounds with water so the ancient ruins and weak wood platforms are not the best footholds.
Abandoned after the downfall of the royal family, Kingdom Valley houses the majestic palaces that once hosted grand galas and magnificent ceremonies. Now, the crumbling castles are slowly falling into disrepair, with no help from Dr. Eggman’s mech army. His mechanized forces have taken up position within the once-impregnable walls of the royal stronghold. Sonic the Hedgehog must cross the valley in pursuit of Princess Elise before Dr. Eggman evacuates Soleanna and discovers how to unlock the Flames of Disaster. Fortunately, now that Silver the Hedgehog has come to realize that Sonic is not the threat Silver once believed, the psychic hedgehog joins the cause to stop Eggman before he is able to ruin the future.
The first part of the Stage is Sonic running through ruins and trying to reach the Egg Carrier. The second part is Silver helping Sonic to reach Elise. It utilizes a High-Speed area at the end which takes place in a set of ruins encircled by rushing water that Sonic also needs to run along. This is the fourth and final high-speed area, after Wave Ocean, Crisis City and Radical Train.
Shadow the Hedgehog and Rouge the Bat head for Kingdom Valley out- side Soleanna, the grand castles that were once home to the monarchy, but now have crumbled into dust. Dr. Eggman’s robots currently occupy the ornate structures, though, giving Shadow ample targets for his chaos- fueled attacks. The waters and skies of Kingdom Valley are treacherous, and Shadow must rely on his Jet Glider and Hover Craft to push through the robotic resistance. However, when ancient doors cannot be unlocked by force, Shadow must call upon Rouge to help him hunt down a set of keys hidden in the castle by Eggman’s minions. After the stage has been completely opened up, Shadow must ride the wind and seek the exit in order to escape Kingdom Valley and push closer to the truth about Dr. Eggman’s schemes.
Shadow's version is not hard and has basic enemies to defeat like Egg Flyer, Egg Gunner, Egg liner and Egg Cannon. Shadow will also has to ride a wind rail and an Eagle to complete the stage and as well control Rouge to find three keys. Do not use the Homing Attack to run the Green Orb to use the wind rail when Shadow is in the Chaos Boost state Because Shadow will not do the Homing Attack but instead he will fall into water.
After completing the stage, Shadow is then ambushed by Dr. Eggman at the extraction point, which leads to Mephiles being released and taking Shadow's form. Mephiles then sent Shadow and Rouge into the future to Crisis City. Shadow later returns here to find the red Emerald in the End of the World.
Silver the Hedgehog makes his way to Kingdom Valley, the site of the royal residences, where the Duke of Soleanna lived prior to the scientific accident that forced him to seal the Flames of Disaster in his only child, Princess Elise. Silver must inﬁltrate the valley, battling back an army of robots in order to meet up with Sonic, who is also raising the majestic valley in his efforts the thwart Dr. Eggman. If Silver and Sonic can catch up with Dr. Eggman’s cruiser and rescue the princess before Eggman is able to release the ﬂames, perhaps they can restore Silver’s future.
Silver's act is considered the hardest, except of Sonic's section. having Egg Hunters, Egg Cannon,Egg Searcher, Egg Walker, Egg Armor, Egg bomber and a lot of Egg Launcher.
In Sonic's story, the player can skip over Silver's part of Kingdom Valley and finish the Action Stage without him by using the Purple Gem.