The Nicky Henderson-trained Buveur D'Air will attempt to defend the crown he won 12 months ago, while Willie Mullins' Faugheen, the 2015 hero, has to redeem himself after being pulled up at Leopardstown over Christmas.
Interestingly, the pair are both entered for the BHP Insurance Irish Champion Hurdle at Leopardstown on February 3, although Henderson has indicated an alternative race at Sandown would be the preferred option for his charge.
Mullins has a total of six possibles for the Cheltenham showpiece, with Melon, Yorkhill and Min among them.
Henderson's support team includes three-times Champion Hurdle runner-up My Tent Or Yours, Call Me Lord, Charli Parcs and Verdana Blue.
Mullins' big rival in Ireland, Gordon Elliott, has Apple's Jade, Mick Jazz and Campeador among the contenders.
The other two Irish entries are outsiders Arcenfete and Idenity Thief, both supplied by Henry de Bromhead.
Arcenfete, a winner on the Flat for the Wertheimer brothers and now owned by Gigginstown House Stud, has not raced since recording a comfortable victory on his jumping debut at Auteuil in June 2016.
"Arcenfete is just coming back and seems nice," said De Bromhead.
"We are hoping to get him out at the end of the month. There is a two-mile conditions hurdle at Naas on January 28 and we are aiming towards that.
"It is only a very tentative entry in the Champion Hurdle. We felt it was better to have him in than not.
"Identity Thief is good and worked nicely the other day. We are also aiming towards the end of the month with him, possibly in the same race at Naas."
Other notable contenders include Nigel Twiston-Davies's popular 10-year-old The New One and last season's Triumph Hurdle hero Defi Du Seuil, trained by Philip Hobbs.
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