Dioscorea (Testudinaria) elephantipes is a nice caudex plant. It will develop a caudex which seems to resemble an elephant foot. The caudex can get extremely large over time.
Do not overwater Dioscorea elephantipes plants because the caudex is sensitive to rot.. The plant requires a gritty soil mix but not too mineral in composition. It requeris some nutrition in the soil.
Keep Dioscorea elephantipes warm in summer and water when leaves and stems are growing. Do not water in winter at a temperature around 5-10 °C.