The Coral-Eclipse winner has emerged victorious on each of his three outings this season and was following up a Royal Ascot win at Sandown.
Having had his final piece of serious work ahead of a clash with Postponed, Appleby believes everything is in place for another big run.
"He went through the gears nicely, and I was pleased with him. It was nice building work," Appleby told www.godolphin.com.
"He is the same body weight as he was going into the Eclipse, which is surprising because visually he appears heavier. The scales say he is exactly the same, though.
"I would say that he is strengthening and still maturing physically.
"As for the ground at York, he can handle soft, as we saw at Ascot and Sandown, and if it is sound underfoot, it would not worry him either. Being by Kitten's Joy, he would probably appreciate a sounder surface, anyway.
"He stepped up again from Ascot to Sandown, and with The Gurkha (second in the Coral-Eclipse) coming out and winning the Sussex Stakes at Goodwood, the form is very solid."
Hawkbill was the only supplementary entry for the Group One meaning 14 go forward.
They include Roger Varian's Postponed, who was forced to miss the King George with a late setback. Varian has also left in King Bolete.
Aidan O'Brien can chose from King George winner Highland Reel, Derby runner-up US Army Ranger and Sir Isaac Newton.
King George runner-up Wings Of Desire has been left in by John Gosden while Kevin Ryan's consistent The Grey Gatsby could have a third crack at the race having placed in both 2014 and 2015.
Prince of Wales's Stakes winner My Dream Boat, William Haggas' Summer Mile winner Mutakayyef and David Lanigan's Almodovar are other strong contenders.
There is French interest in the shape of Alain de Royer-Dupre's Dariyan while Sir Michael Stoute has Arab Spring and Exosphere in the mix.
G2 - The Sky Bet Supreme Trial Novices' Hurdle Race (class 1)
G2 - The Stanjames.com Champion Hurdle Trial (class 1)
G2 - The Peter Marsh Steeple Chase (a Limited Handicap)
G2 - The Altcar Novices' Steeple Chase (class 1)
G2 - The Olbg.com Mares' Hurdle Race (class 1)