Following are all the darkening like words, in the list below.
DARK
100% like darkening
BLACKENING
99.95% like darkening
FADING
50.06% like darkening
BRIGHTENING
50.06% like darkening
BLOTCHING
50.06% like darkening
DIMMING
50.06% like darkening
DISCOLORING
50.06% like darkening
TINGEING
50.06% like darkening
DISCOLORATION
50.06% like darkening
DAPPLING
50.06% like darkening
LIGHTENING
50.06% like darkening
DULLING
50.06% like darkening
THICKENING
50.06% like darkening
REDDENING
50.06% like darkening
CLOUDING
50.06% like darkening
DIMINISHING
50.06% like darkening
DARKNESS
50.06% like darkening
DARKER
50.06% like darkening
DISCOLOURING
50.06% like darkening
SOFTENING
50.06% like darkening
TATTERING
50.06% like darkening
SPLOTCHING
50.06% like darkening
DIMNESS
50.06% like darkening
GLOOMING
50.06% like darkening
DEEPENING
50.06% like darkening
GREYING
50.06% like darkening
DUSKINESS
50.06% like darkening
LENGTHENING
50.06% like darkening
DISCOLOURATION
50.06% like darkening
SPECKLING
50.06% like darkening
THINNING
50.06% like darkening
SPANGLING
50.06% like darkening
STAINING
50.06% like darkening
GRAYING
50.06% like darkening
SALLOWNESS
50.06% like darkening
SILVERING
50.06% like darkening
WORSENING
50.06% like darkening
SHADOWS
50.06% like darkening
DETERIORATION
50.06% like darkening
ILLUMINING
50.06% like darkening
STREAKING
50.06% like darkening
HARDENING
50.06% like darkening
FLECKING
50.06% like darkening
SHRINKING
50.06% like darkening
TINTING
50.06% like darkening
SEEPING
50.06% like darkening
GRAYNESS
50.06% like darkening
LIGHT
50.06% like darkening
RUDDINESS
50.06% like darkening
BLUISH
50.06% like darkening
MISTINESS
50.06% like darkening
OBSCURING
50.06% like darkening
SUFFUSION
50.06% like darkening
TINGING
50.06% like darkening
BROADENING
50.06% like darkening
WEAKENING
50.06% like darkening
RIPPLING
50.06% like darkening
WARPING
50.06% like darkening
CREEPING
50.06% like darkening
ENLARGING
50.06% like darkening
LIGHTEN
50.06% like darkening
BLEMISHING
50.06% like darkening
SHINING
50.06% like darkening
GREYNESS
50.06% like darkening
BLACKNESS
50.06% like darkening
ENCROACHING
50.06% like darkening
VANISHING
50.06% like darkening
FRECKLING
50.06% like darkening
LESSENING
50.06% like darkening
CLOUDINESS
50.06% like darkening
BLURRING
50.06% like darkening
BRIGHTNESS
50.06% like darkening
SUFFUSING
50.06% like darkening
RECEDING
50.06% like darkening
SHADOW
50.06% like darkening
DISCOLOURATIONS
50.06% like darkening
DARKEST
50.06% like darkening
CORRODING
50.06% like darkening
ROUGHENING
50.06% like darkening
CHANGING
50.06% like darkening
FLICKERING
50.06% like darkening
EFFECT
50.06% like darkening
GLOW
50.06% like darkening
REDUCING
50.06% like darkening
REDNESS
50.06% like darkening
ENHANCING
50.06% like darkening
BLEACHING
50.06% like darkening
INTENSIFYING
50.06% like darkening
DAPPLED
50.06% like darkening
OVERCASTING
50.06% like darkening
DISAPPEARING
50.06% like darkening
WISPING
50.06% like darkening
BURNING
50.06% like darkening
TARNISHING
50.06% like darkening
TINT
50.06% like darkening
TWILIGHT
50.06% like darkening
CRISPING
50.06% like darkening
SUNBURNING
50.06% like darkening
GRAYISH
50.06% like darkening
SHADING
50.06% like darkening