How did Rickert survive?

sorry to post this but Rickert obivously survived but how? That confused me.. Sorry for the new thread if it has been answered before.

Thank you.

He was with the part of the Hawks that stayed behind while the others went to free Griffith. When they got attacked and killed by the Snail Count and Roshinu's minions, the Skull Knight appeared and held them back at the last moment, saving Rickert's life (all the others were dead already, slaughtered while he had been getting water from a nearby river). He then joined a group of travellers, which coincidentally had Puck with them (and he later treated Guts and Casca's wounds using Elf dust).