Then think again!
Brine -- Grass Knot -- Brine
IF Onix uses a D/E move NOT suspended AND NOT in a combo, THEN replace all instances of Brine with Brine + Brine and all instances of Grass Knot with Grass Knot + Grass Knot, but only for the current action
IF Onix is under the effects of a succesful P/E move, THEN use Ingrain first instance, Chill second instance