活血

活 = 氵 + 舌 : Helga Horse joined the traditional water bottle challenge and empties a bottle of water over herself in the observatory's kitchen. To raise the difficulty level, she only uses her tongue to hold the bottle.

血 = 丶 + 皿 : Mnemonic symbol: blood transfusion.

Xu Xian hurt himself and needs to get a blood transfusion in the elevator's bathroom. He found a petal leaf as donor, which is bleeding droplets into a bowl; Xu Xian gets the blood from the bowl as infusion using some tubes.