It is an older screenshot, from a time when I did have Hellhound. But even back then, I only had 1 point in it just for an extra pet and it wasn’t doing much. So I took it out. Same goes for Blightfiend.
For starting out, refer to beginner builds since they are mostly made with faction items and such which are easy to get. Looks here for more information: The Carnival - A Guide to Pets
If you want a more indepth or detailed response regarding something, feel free to let me know 