Minecraft wiki entry for Advancement_guide, associated text: Once you have a strider in range of you, use it with the saddle to saddle it. If there is a zombified piglin or a baby strider on top of the strider, then you will have to choose a different strider. However, zombified piglins are good, because the strider which is riding the zombified piglin will have a saddle already equipped on it. There is a 1 in 30 chance of a zombified piglin riding a strider. If that is the case, try killing the zombified piglin. Then, you will have an already saddled strider.