To dream that you kill one, shows that you will overcome difficulties and enemies, and be successful in love, trade, and farming. The snake is also a symbol of passion and sexual desires.
Dream dictionary: seven headed snake dream meanings
(Snake pit. See Tongue)
…Walking through fields of fragrant clover is a propitious dream. It brings all objects desired into the reach of the dreamer. Fine crops is portended for the farmer and wealth for the young. Blasted fields of clover brings harrowing and regretful sighs. Dreaming of clover, foretells prosperity will soon enfold you. For a young woman Dreaming of seeing a snake crawling through blossoming clover, foretells she will be early disappointed in love, and her surroundings will be gloomy and discouraging, though to her friends she seems peculiarly fortunate….