Ireland centre Bundee Aki will lead the Barbarians against England for the non-cap fixture at Twickenham.
Aki, a Grand Slam winner who has won on all seven of his starts for Joe Schmidt's men, is joined by Wales openside Justin Tipuric and Scotland scrum-half Greig Laidlaw among the 17 players confirmed so far for the May 27 fixture.
Also included are Ireland-capped lock Ultan Dillane and scrum-half Rhodri Williams, who has represented Wales.
"The big thing about Bundee is that he's an unbelievable competitor," said Barbarians and Bristol head coach Pat Lam, who signed Aki for Connacht from the Chiefs in 2014.
"A lot of the Pacific Island boys have that X-factor but he loves putting his head in the dark places and thriving in turnover and contact work.
"England is a game we're going to have to work hard in and he epitomises what we need to do. We need the courage to play and move the ball and also to know when we have to tighten things up, and he'll be at the centre of that."
Bristol-bound former New Zealand full-back Charles Piutau is among the 17, as are his fellow All Blacks Victor Vito, John Afoa and Luke McAlister.
The Barbarians have faced England 16 times and are seeking a first win since their 39-29 victory in 2014.
Backs: N Adeolokun (Connacht and Ireland), B Aki (Connacht and Ireland), G Laidlaw (Clermont and Scotland), L McAlister (Toulon and New Zealand), AJ McGinty (Sale Sharks and USA), C Piutau (Ulster and New Zealand), R Williams (Dragons and Wales)
Forwards: J Afoa (Gloucester and New Zealand), U Dillane (Connacht and Ireland), R Herrera (Stade Francais and Argentina), B Kayser (Clermont and France), T Polota-Nau (Leicester and Australia), S Timani (Clermont and Australia), J Tipuric (Ospreys and Wales), L Uhila (Clermont), F van der Merwe (Clermont and South Africa), V Vito (La Rochelle and New Zealand)