Kill an adult - quickest way is flamethrower, grab the seed off its body. Plant the seed in a plot. Will ask you to use the following to “tend” - this is the taming. It will ask for any number of any of them throughout the process so have many prepared.

- Leech Blood

- Bio Toxin

- Sap

- Ammonite Bile

- Giant Bee Honey

- Black Pearls

If you tame Elderclaws and breed them: the seed you plant will not ask for anything and will just grow.