Allaho, Gerri Colombe and last year's winner Bravemansgame are among eight confirmations for the Ladbrokes King George VI Chase at Kempton on Boxing Day.
Willie Mullins sprang a surprise in the race two years ago with Tornado Flyer but that was his first triumph in the race since Florida Pearl in 2001 and in Allaho he has strong claims of a second success in three years.
A dual Ryanair Chase winner, Allaho was being aimed at the three-mile contest last year but picked up an injury which ruled him out of the whole campaign. He returned to action with a win in the Clonmel Oil Chase.
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Gerri Colombe has only met with defeat once in his career, at last season's Cheltenham Festival behind The Real Whacker, and the two could clash again, although Gordon Elliott also has the option of running Gerri Colombe in the Savills Chase at Leopardstown on December 28.
Only a short head separated them at Cheltenham but their fortunes have differed wildly since, with Gerri Colombe winning two Grade Ones at Aintree and Down Royal, while The Real Whacker was pulled up in the Paddy Power Gold Cup - having struck into himself.
Paul Nicholls' Bravemansgame is without a win since his victory 12 months ago - he went out on his shield in the Cheltenham Gold Cup when second to Galopin Des Champs but has been surprisingly beaten in the Charlie Hall and Betfair Chase this season.
He will be joined by stable companion Frodon, winner of the race in 2020 and third last year when Royale Pagaille, who is also entered again for Venetia Williams, was second.
Shark Hanlon's Hewick is also set to take his chance, while Shishkin is the unknown quantity in the field after refusing to start at Ascot recently. He proved his stamina for three miles at Aintree in the spring but the lack of a recent run is a concern for his trainer Nicky Henderson, who withdrew his charge from the Fighting Fifth Hurdle at Sandown earlier this month due to the ground.
Henderson said: "I've been saying all along I don't see how you can win a King George without a race and the answer is you can't. On the other hand, we have got nowhere else to go as there isn't another race until the Cotswold Chase.
"If I ran him at Sandown I would have bottomed him and he wouldn't go to the King George, so therefore I had to take him home and run him straight in this.
"Having said that he has been going, for him, really well, and his schooling the other morning was fantastic. I'm not going to sit here and tell you he can win a King George, but I do think he can run very well.
"He is the sort of forgotten person in the race, and no one has mentioned him. The only thing I would say is don't judge him on this because I think it is very unfair coming into a race like this without a run.
"It doesn't mean there aren't bigger and better things to come. He might run very well and not quite get home [in front]."
Henderson is confident there will be no repeat of his Ascot antics down at the start of the King George after taking steps to ensure a similar scenario will not occur.
The Seven Barrows handler added: "George (Daly, assistant trainer) will go down to the start with him as he knows him really well. We can't do anything else.
"Charlie Brooks mentioned a hunting horn, but Barney (Clifford, clerk of the course at Kempton) won't let me get up a tree and blow it!"