Succumbing rhymes with:
becoming, coming, cumming, forthcoming, unbecoming, becoming, coming, cumming, drumming, dumbing, forthcoming, humming, numbing, plumbing, strumming, summing, thumbing, unbecoming
Succumbing sounds like:
sampans, semifinish, signifying, skimping, snapping, sniffing, sniping, snooping, snubbing, snuffing, sunbeam's, swamping, symbion's, symphonic, symphonies, symphony's