None of your Barbarian feats will aid you here, and in fact will interfere if you grow larger than the mount can handle.
Can you play a tiny sprite riding a corgi into battle?
Very much yes, and Barbarian makes a fine warrior. But for all the benefits of using a mount, it's not gaining your PC's feats nor Rage. You have a choice between gaining the movement bonuses from using a mount or from your class feats, but they don't stack nor interact. And if you have to use Moment of Clarity too, I'd say you're breaking even at best (with the downside of having a vulnerable creature alongside you).
I wouldn't say it's the rules limiting what cool things you can do, as the abilities give you exactly what one would expect from them. It's that there's poor synergy between "cool thing A" & "cool thing B". Trying to use Giant's Stature on top of that, that's silly IMO.
Meanwhile, a Ranger could look feral (or have whatever barbaric imagery you're going for) yet have much better synergy & payoff from riding a mount.
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Rules aside, there could be ways to reskin this for the imagery you want, and there are shenanigans (with spells for example) to increase the corgi's size too. But the former requires GM permission (and might feel wonky), while the latter would be outright wonky, requiring lots of feat investment and actions to implement with very little payoff.
Giant Instinct is just an extremely poor fit for a moutned combatant. In PF1 there was an archetype (IIRC) that let your mount benefit from your rage and stuff, but nothing like that exist in PF2 as far as I'm aware.
If you chose a different instinct you would probably be alright.
Also, keep in mind the corgi is a familiar and not even an animal companion. So they can't attack.
If you want to have a Corgi and use it in battle then buy it as a Canine Animal companion.
If you want to be raging and riding an animal companion then it is best that the animal is Mature so it can take a free action to move and you don't have to waste two actions to moment of clarity and command it each turn. It can work OK.
Being a Giant is OK provided you don't take Giants Stature and become large. It still does all its damage anyway. But most people want to. So then you need to talk with your GM so you can get your animal companion to size huge. The normal progression won't give you a Huge or Gigantic size mount. By default it caps at large (outside of a level 4 enlarge spell or the Beastmaster spell Enlarge Companion or the Druid capstone Apex Companion) Most GMs should give it too you as long as you don't try too hard to exploit it too much. Mammoths should really get to size huge naturally. I don't know about giant Corgis though.
The other technically is that there is no rule saying what happens when you size chage (you start raging and go into Giant Stature) while already mounted. It is up to the GM.
Check out how the reach rules change
If you want to have a Corgi and use it in battle then buy it as a Canine Animal companion.
Yeah, that will work but it wont be a "Corgi mount" it'll be an small size dog that is being flavored as a corgi. The bigger issue is while Sprites can pick up corgi mount as a first level ancestry feat, getting an animal companion requires picking certain classes or multiclassing, which wont be available at level 1.
If you want to have a Corgi and use it in battle then buy it as a Canine Animal companion.Yeah, that will work but it wont be a "Corgi mount" it'll be an small size dog that is being flavored as a corgi. The bigger issue is while Sprites can pick up corgi mount as a first level ancestry feat, getting an animal companion requires picking certain classes or multiclassing, which wont be available at level 1.
The whole point is how you do it in the rules. Raging on a familiar is just not going to be reasonable. End of story.
The whole point is how you do it in the rules. Raging on a familiar is just not going to be reasonable. End of story.If you want to have a Corgi and use it in battle then buy it as a Canine Animal companion.Yeah, that will work but it wont be a "Corgi mount" it'll be an small size dog that is being flavored as a corgi. The bigger issue is while Sprites can pick up corgi mount as a first level ancestry feat, getting an animal companion requires picking certain classes or multiclassing, which wont be available at level 1.
You're coming across as a bit hostile, when I was generally agreeing with you but wanted to point out the cost to the OP.
It sounds like the OP may already be playing this character in which case the may be stuck with the Corgi mount familiar. If that is not the case, then yes they can make this work (more or less) by multiclassing into something with easy access to an animal companion. It's still not going to get rage benefits, which makes it still kind suck. Because if the OP takes giant stature (which sounds like the point of being a giant instinct barbarian for them) then they wont be able to ride their companion because they will grow to large and require a huge companion which I don't believe is available. Later they could grow to huge, and then they're definitely SOL because no companion will grow big enough for a huge creature to ride for sure.
You're coming across as a bit hostile.
Then think again.
You're coming across as a bit hostile.Then think again.
Your phrasing is certainly very ... Pointed, I get where claxon is coming from
You're coming across as a bit hostile.Then think again.
It may not be your intention, but you're certainly not presenting a good case for another conclusion.
You are definitely being terse, which comes across as unfriendly. It may not be your intention, but as our conversation is only text, and people (myself included) try to read a "voice" into the conversation, your laconic statements aren't endearing.