Argentina winger Emiliano Boffelli will make his first appearance of the season for Edinburgh when they host Lions on Friday night.
Dragons have confirmed a mass exodus of players from the club which now amounts to a total of 20 athletes since the season began.
Leinster moved four points clear at the top of the United Rugby Championship following a 21-13 win over the Lions at the RDS Arena.
Two tries from back-rower Nick Timoney ensured Ulster made it four bonus-point wins from four as they defeated the Lions 26-10 at the Kingspan Stadium.
The match will see the return to action of Jaco Kriel, who left Premiership side Gloucester at the start of the year to return to SA and the Lions earlier this year.