WordNet sense 1 (not to be trusted):

tricky

WordNet sense 2 (not worthy of trust or belief):

untrustworthy, untrusty

WordNet sense 3 (having a slippery surface or quality ):

slithery

WordNet sense 4 (covered with or resembling slime):

slimy

WordNet sense 5 (made slick by e.g. ice or grease):

slick

WordNet sense 6 (causing or tending to cause things to slip or slide):

slippy