accelerate
acerbate
agent provocateur
aggravate
alienate
amplify
annoy
antagonize
augment
beef up
bitter
blow up
build up
chafe
complicate
concentrate
condense
consolidate
damage
deepen
deteriorate
dilapidate
double
embitter
endamage
enhance
enlarge
envenom
estrange
exaggerate
exasperate
feed the fire
fret
gall
grate
grate on
gravel
grit
harm
heat up
heighten
hop up
hot up
hurt
impair
increase
inflame
infuriate
injure
anger
exacerbated
exacerbates
exacerbating