Cyrname heads a field of five as he bids to regain his Betfair Ascot Chase crown on Saturday.
Paul Nicholls' chaser won the race in devastating style in 2019, but was beaten when falling 12 months ago.
His season started in perfect fashion this time around with an easy victory in the Charlie Hall Chase at Wetherby, but he disappointed in the King George on Boxing Day and needs to bounce back.
Having worn a hood in his early days due to his exuberant tendencies, Nicholls has declared the nine-year-old in cheekpieces.
Of the decision to run in cheekpieces, Nicholls told Sky Sports Racing: "I just think he was getting a bit lazy, racing behind the bridle, which isn't like him.
"We worked him in them, and they made a big improvement. It's just to sharpen him up really.
"He'd just got lazy. He used to be a tearaway and very free in his races, but it certainly sharpened him up in his work.
"Obviously he's a challenge to train in lots of ways. When he's right he's a very good horse, and hopefully he'll run like he did in the Charlie Hall.
"If he has a hard race this weekend it's too close to Cheltenham, so Aintree may well suit him well, but let's get this out of the way. The Oaksey Chase at Sandown could suit him too."
Nicholls also runs Master Tommytucker - who will be ridden by Daryl Jacob, with Harry Cobden aboard Cyrname.
"He's in great form and looks good," said Nicholls.
"He doesn't have to make it (the running). He can take a lead, but they'll be going a good gallop if Cyrname is at his best, (so) hopefully Tommy can slot in just behind him.
"He's a very talented horse in his own right. I think he'll run very well.
"Sam Twiston-Davies has won on him but had to ride his dad's horse, so I'm looking forward to seeing how Daryl gets on with him."
Nigel Twiston-Davies' Riders Onthe Storm had gone clear of Cyrname before the latter's exit in last year's event.
At the time he was on the crest of a wave, but he has struggled to recapture his best form so far this season.
One horse certainly on the up is Jeremy Scott's Dashel Drasher, who has won his last two races over course and distance. This represents a big step up in class, but the eight-year-old has always been a promising type.
Just behind him last time was Dan Skelton's Bennys King, and the pair meet again.
Six have been declared for the Bateaux London Reynoldstown Novices' Chase, in which Fergal O'Brien's Hurricane Harvey has to carry a penalty for his victory at Doncaster.
Oliver Sherwood's Sevarano takes his chance, while Kalooki represents Philip Hobbs.
Kerry Lee's Demachine, Gary Moore's Full Back and the David Pipe-trained Remastered complete the field.
Nicky Henderson's Gallyhill runs in the opening greatbritishstallionshowcase.co.uk Novices' Hurdle, with Ascot specialist Regal Encore carrying top-weight in the 'My Oddsboost' On Betfair Swinley Chase.