Better known as 'Ligtoring' to his teammates, the 27-year-old lock will join up with the Dragons squad in the summer to bolster Lyn Jones' options in the tight five.
The second row who can also pack down as flanker played youth and senior rugby with the Leopards. He then moved onto the Boland Cavaliers in 2011 before making the change to play for Griquas in the 2012 Currie Cup.
Strong performances for the Griquas gave Landman the chance to showcase himself at Super Rugby level with the Cheetas in 2013 where he made 14 appearances in the 2013 super rugby season forming a strong partnership in the second row in the Cheetahs run to the play-offs.
The South African is a strong ball carrier, good lineout operator and is mobile throughout the game. On signing the Landman, Lyn Jones commented, "I am delighted that we have recruited Rynard. Its another piece of the jigsaw and an important signing in the development of the region.
"He will offer size, strength and experience to the second row and will act as a catalyst in the growth of our current crop of young Welsh locks.
"Not only will Rynard will be a real physical presence in the pack but he will help to bring along Matthew Screech, Cory Hill and Joe Davies."
Landman becomes the regions seventh recruit for next season following the signings of props Boris Stankovich and David Young, hooker Rhys Buckley, lock Ian Gough, wing Aled Brew and full-back Lee Byrne.
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