[Yumyums Inmahtumtums]

They're great for soloing even if only for the reclaim energy insta click.

They boost the hp of each respective pet type to the next pet.

Fire pet with torch = hp of air pet without.
Air pet with broom = hp of water pet without.
Water pet with stein = hp of earth pet without.
Earth pet with torch = higher hp earth pet.

Also they're bigger which is cool too. It makes soloing with fire pet much more viable.