The second and third home in 2016, Highland Lodge and The Last Samuri, have also stood their ground, but it's Blaklion who is Sky Bet's 4/1 favourite.
His trainer Nigel Twiston-Davies has won this race five times relies on the Grand National fourth.
He ran well on his seasonal debut when only beaten half a length by Bristol De Mai in the Charlie Hall Chase at Wetherby.
Highland Lodge, trained by Kim Bailey, tops the weights on 11st 12lb while David Pipe's Vieux Lion Rouge has 11st 5lb and Highland Lodge 10st 5lb.
Jimmy Moffatt reports Highland Lodge to be in prime shape as he bids to repeat his triumph of 2015.
"He's in great form. He's had exactly the same preparation as last year and he's going every bit as well. I've no doubts in my mind about that whatsoever," said the Cartmel trainer.
"He's really come alive in the last two or three weeks and his wind-up gallop on Saturday was probably one of the best pieces of work I've seen him do.
"I couldn't be happier with him.
"This has been his long-range target so he's been in since the end of July. He's had a good long steady build-up."
Other smart performers in the mix include Scottish National winner Vicente, Sizing Codelco, As De Mee and Gas Line Boy.
Trainer Paul Nicholls said: "As De Mee goes in the Becher Chase. I have left him in the Grand Sefton as well, just in case the ground gets very testing, but I intend to run him in the longer race."
However, Nicholls revealed Scottish National scorer Vicente will sidestep the Becher and instead would run in the 188Bet.co.uk Many Clouds Chase on the same card instead.
"Vicente won't be running the Becher Chase but he could head to Aintree on Saturday for the Many Clouds Chase instead," he said.
"I was very pleased with him at Cheltenham (second) and he has come out of that race well."
The four Irish-trained possibles are Jim Culloty's 2014 Cheltenham Gold Cup hero Lord Windermere, Mouse Morris' 2016 Irish National scorer Rogue Angel, Pat Griffin's Portrait King and Eoghan O'Grady's Westerner Point.
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