Player: elise
Character: percy jackson
Item: Mrs. O'leary! quoting the wiki as far as her appearance goes:

"Mrs. O'Leary is very scary and described as a mastiff. She is unnaturally large, even for a hellhound. Percy describes her as "bigger than a tank and barks slightly louder than an artillery gun".

Mortals, on at least one occasion, see her as a large standard poodle, rather than an impossibly big dog."

she has the ability to shadow travel, which is basically teleporting through shadows. but she's only able to do it a couple of times at best before she needs to rest.
Questions: nerf away! if a dog that's as big as a tank is too big (lol) we can always go with the large standard poodle approach!