You can grasp things with your tail. It has a reach of 5 feet. It can lift, as much as you could with one arm and can be trained as you would your arm as-well. You can use it to do the following simple tasks: lift, drop, hold, push, or pull an object or a creature; open or close a door or a container; grapple someone; or make an unarmed strike; hang from a piece of scenery. Your DM might allow other simple tasks to be added to that list of options.
As a bonus action, you may:
- Gain advantage on Grapple checks.
- Attempt to shove someone.
Your tail can wield weapons of the light class however this does not include shields or anything wielded with 2 hands but you learned to operate one tool in which you are proficient with your tail. You also learned how to perform the somatic components of spells with your tail.
You also gain a tail swipe which does d4 + dex or if your have proficiency in unarmed attacks d6 + dex and increases with your lv (if your a monk/fighter use monk/battle master die for this)
And finally you gain Tail sweep which attempts to trip your opponent and knock them down (dex save dc spell mod + proficiency bonus) on fail d4 + dex on save you take no damage
At level 7 you gain the ability to attack people entering your space as a reaction you can use your tail to either attempt to swipe them or trip them with the tail (Save dex dc spell save) or for swipe (to hit then dex + prof)