Unmitigated rhymes with:
mitigated, mitigated, castigated, instigated, mitigated, abrogated, castigated, instigated, interrogated, irrigated, mitigated, navigated, obligated, propagated, relegated, segregated, subjugated
Unmitigated sounds like:
unadjust, unadjusted, unattached, undecided, undetected, undisguised, uneducated, unhedged, unindicted, unmatched, unnoticed, untaxed, untested, untouched