They seem to have altered the tame methodology recently. Very, VERY low level Moschops, 10 and below, will take specific berries instead. I'd just spawned in and was gathering fiber when a level 8 walked by with the blue text asking for a Tintoberry to tame.
Pro tip: Best and easiest tame to get LARGE EGGS for kibbles, tame a few low leveled ones, 1 male and 4 females is enough to get your kibble farm started.
Use the kibbles to kibble tame high leveled argy and others. I give this useless guy 5 out of 5 stars just because of her their eggs.
Give this an up to let everyone know this.
I had a massive family of casteroides causing trouble and building dams near my base, but after a while they migrated elsewhere, and left the dams all for me! I raided the dams, got 126 rare mushroom, and fed up a moschops lvl 36 with it! He is a living fibre farm!