I have tamed ice cave direwolves on mobile in brutal mode. Try to tame a male and have him come out at level 1000. Breed him with low level females or level 890 females and go for the perfect level 940 babies. Zero mutations on one of my perfect pups and pumped all 60 levels into speed. With a gold collar and breeding bonus the dogs reach max speed of 449.9% which is hella fast. My tanky dogs with nearly capped riot and flak helmets can take on level 300-450 gigas until the hat breaks. Still experimenting with this. Max melee and health is the goal.