So, mythic characters get a lot of power ups throughout their 10 tiers. However, from what I'm seeing, I don't think animal companions, summons, and eidolons are going to be able to keep up with the power increases.

There are a few abilities that allow you to give your pets mythic power, epic DR, and the ability to move and make an extra attack. However, these powerups, while good, won't let them fight that much more effectively against high CR opponents. They aren't gaining feats, hit points, or the primary stat increases that mythic characters are getting.

Personally, I would recommend that there be a few mythic abilities that give a character's animal companions, summons, eidolons, and any other 'pets' scaling bonus' similar to the ability score boost that Mythic Characters get every two mythic tiers. Additionally, there probably should be a Path Ability that can be chosen to allow eidolons or animal companions to gain Mythic Feats.

I would even go so far as to say that you may want to put in mythic tier tables specifically for pets, and let the pets automatically gain those tiers at the same rate as the characters they belong to.

Yea, this is all theorycrafting, but it does seem to me that 'pets' will fall behind in power with the current system. I apologize if these sorts of things are already planned but just aren't in the current playtest ;)

I agree with that. At this point a pet class like a summoner or druid who focuses on making his companion awesome will have a hard time in Mythic. I'd recommend an ability to grant a simple mythic template to the companion.

After all what would He-Man be without Battlecat?
The Lone Ranger without Silver?
Drizzt without Guenhwyvar?

This is just playtest 1. Remember, the Alpha for PfRPG came out in 3 stages, and at first all we had was Clr/Ftr/Rog/Wiz. It wouldn't surprise me to see at least three releases before the final hardback hits GenCon 2013.

I agree.

Make it either a part of the Marshal or Hierophant and there you have it.

Mythic Pounce -- I mean, Beasty Fury -- is pretty good if you have lots of swift actions..

This is just playtest 1. Remember, the Alpha for PfRPG came out in 3 stages, and at first all we had was Clr/Ftr/Rog/Wiz. It wouldn't surprise me to see at least three releases before the final hardback hits GenCon 2013.

Right, but we have no way of knowing which parts are intentionally missing and which are problems that we need to point out. So, there is no harm in pointing out that companions are aren't getting enough in the current version ;)

This can all easily be solved by a separate Mythic path called "Mythic Companion." Some of us are not all that special but sometimes in the company of a truly extraordinary person we're pushed to limits we never thought possible. There's always someone special that brings the best out of us, we work harder, we do things better, we behave at our best. Well we were at that time the Mythic Companion to a Mythic Person.

The Iolaus to Hercules, Robin to Batman, Simon to Kamina, Arthur to The Tick. The trusty steed, the true friend, the loyal family pet. They're never anything incredibly special really but they always had a friend that saw something special in them and they end accomplishing really great things in the presence of very superior people.

This is more than enough to support a Mythic Path that only eidolons, animal companions, summons, cohorts, etc can take. They're mythic flaw could be that they have to be the companion of a Mythic Character and once they're no longer the companion they lose this Mythic Path. Their Mythic tier will match the Mythic Character's tier. You can keep all the standard Mythic Tier abilities that the PCs get even up to immortality cause there's always a scene where a friend dies and they come back to life miraculously. The benefits of a Mythic Companion path are that players don't have to feel shoehorned into a support path and companions keep up with the power of the PC especially if it's a class that relies on companions.