Cardiff’s Welsh Six Nations squad member Harry Robinson is among six Blue & Blacks called in to Wales Under-20's Junior World Championship campaign in June.
Up front Willgriff John, Matthew Screech, Luke Hamilton and Ellis Jenkins are selected, in the backs Thomas Pascoe joins Robinson to complete Cardiff’s squad members.
Wales face New Zealand, Fiji and Samoa U20s at the pool stage.
Robinson and Dragons centre Jack Dixon played limited roles in the Under-20 Six Nations, the former playing in the 40-9 defeat by England and Dixon in the 30-23 win over Italy.
Along with Prydie, Morgan, Walker, Hamilton, Hill and Ospreys scrum-half Tom Habberfield, Dixon and Robinson were involved in regional duties while the junior Six Nations was underway.
Coach Danny Wilson said: "The players who have joined the squad since the Six Nations have already brought a new intensity to our training sessions and we hope that their regional and international experience will help lift our playing performances too.
"The additional players have certainly improved our strength in depth, but now we must have a good month training in order to get on the plane feeling well prepared.
"It is an extremely physical group and we must meet that challenge head on if we want any chance of progressing to the top half of the draw."
New Zealand U20, who have won the last four JWC tournaments, beat Wales 92-0 at the 2011 event in Italy in which Wales finished seventh. Wales also finished seventh in 2010, having been sixth in 2009 and fourth in 2008.
Wilson added: "New Zealand have proved year after year that they are the strongest side in the world at this age, so they will again be a huge challenge. "But we must target our other Pool games against Fiji and Samoa. "We saw last season that those sides are very dangerous and we must execute the right game plan against them. We must be physically and mentally ready for all three games."
Wales Junior World Championship squad
Forwards: Rob Evans (Scarlets), Gareth Thomas (Scarlets), Kirby Myhill (Scarlets), Jamie Sollis (Dragons), Darran Harris (Blues), WillGriff John (Cardiff RFC / Blues), Samson Lee (Scarlets), Cory Hill (capt, Blues), Matthew Screech (Cardiff RFC / Blues), Rhodri Hughes (Ospreys), Ieuan Jones (Dragons), Ellis Jenkins (Cardiff RFC / Blues), Daniel Thomas (Scarlets), Luke Hamilton (Cardiff RFC / Blues), Dan Baker (Ospreys).
Backs: Jonathan Evans (Dragons), Tom Habberfield (Ospreys), Sam Davies (Ospreys), Matthew Morgan (Ospreys), Owen Williams (Scarlets), Jack Dixon (Dragons), Thomas Pascoe (Cardiff RFC / Blues), Iolo Evans (Scarlets), Luke Morgan (Ospreys), Harry Robinson (Cardiff RFC / Blues), Eli Walker (Ospreys), Tom Prydie (London Wasps), Ross Jones (Ospreys).