What It Scores
RISUS is a valid word in the tournament list this site uses. Tile values only, before any premium square: 5 in Scrabble and 6 in Words With Friends. The letters break down as R1 I1 S1 U1 S1.
Words Made From The Letters In RISUS
12 shorter words come out of these tiles. On a board that matters more than the long play, because a short word on a premium square often beats a long one on plain squares.
4 letter words (2)
3 letter words (6)
2 letter words (4)
Longer Words Containing RISUS
RISUS appears inside each of these, which is what makes it worth knowing as a hook.
Next: the Word Unscrambler for any letters at all. Full entry and definition at Merriam-Webster.