Pathfinder Beast Rider

[Uhtred]

So I'm starting a Pathfinder campaign and one of my players is brand new, has expressed interest in being a Cavalier. He did some research on his own and discovered the Beast Rider alternate class features and is totally psyched to be riding a dinosaur, since they're starting at lvl 5 and dinos start to be available at 4. I thought that a level 4 character riding a T-Rex seemed a teensy bit overpowered, so I looked them up in the Bestiary and, helpfully, there are starting statistics for a companion T-Rex. He is medium-sized. How is a medium-sized Cavalier meant to ride one? Do I use the stats provided in the Beast Rider description to make a medium-sized critter large, the Str/Con +2 Dex -2? And will there be a point when the T-Rex's size increases to Huge? My player was really looking forward to Swallow Whole. Thanks in advance!

P.S. are there rules in Pathfinder for putting weapons and armor on a dinosaur? Apparently my player watched a show called Dino-Riders, and the thought of an armored dinosaur covered in cannons and rocket launchers is incredibly attractive to him.

[CTrees]

You use these statistics (http://www.d20pfsrd.com/classes/core-classes/druid/animal-companions#TOC-Tyrannosaurus). As the Tyrannosaurus companion does not become large until seventh level, it is not rideable by a medium character until seventh level (with the stat adjustments listed in that stat block), though you could either handwave it or allow the size increase earlier, with lesser stat increases. It never becomes huge on its own, though there are ways to make it happen.

As far as armoring your dinosaur, that would count as armoring an unusual creature (http://www.d20pfsrd.com/equipment---final/armor#TOC-Armor-for-Unusual-Creatures), modifiying the normal rules for barding listing directly above that section. Note that mounts are affected by non-proficiency just like characters are, if they lack the appropriate armor proficiency feats (rules for mounts or other animal companions gaining feats are on the animal companions page).

[Ravens_cry]

Strong jaw is an awesome spell, and if you get to pick feats for your critter, the Vital Strike line actually adds some significant damage for a T-Rex, or any other critter with one big attack.

[Uhtred]

You use these statistics (http://www.d20pfsrd.com/classes/core-classes/druid/animal-companions#TOC-Tyrannosaurus). As the Tyrannosaurus companion does not become large until seventh level, it is not rideable by a medium character until seventh level (with the stat adjustments listed in that stat block), though you could either handwave it or allow the size increase earlier, with lesser stat increases. It never becomes huge on its own, though there are ways to make it happen.

So is that the draw of the Mammoth Rider prestige class? I believe that they get a mount size increase as a class feature and I was curious why anyone would choose to be a Mammoth Rider instead of a Beast Rider, since Beast Riders get the mounts earlier.



As far as armoring your dinosaur, that would count as armoring an unusual creature (http://www.d20pfsrd.com/equipment---final/armor#TOC-Armor-for-Unusual-Creatures), modifiying the normal rules for barding listing directly above that section. Note that mounts are affected by non-proficiency just like characters are, if they lack the appropriate armor proficiency feats (rules for mounts or other animal companions gaining feats are on the animal companions page).

Dinosaurs get an Int of 2, right? If I use the ability score increase that the cavalier's mount gets every four levels to increase Int to 3 and therefore qualify for any feat he can physically use, Armor Proficiency will be on that list, won't it? And what about the whole "Mounting a cannon on a dinosaur" thing? If he takes Mammoth Rider and has a huge-size T-Rex the thing can theoretically carry some monstrous weight. Any rules about firing a cannon from the back (or side) or an animal?

[Ravens_cry]

I saw a Gatling gun on a camel once, so there is historical precedent (http://en.wikipedia.org/wiki/Zamburak). As for rules, well, there *is* rules for firing from horseback. Not sure about full fledged cannon though.

[stack]

Downside of Beastrider over regular cavalier is that you can't jump into another class after 4 and keep your mount at full power with one feat, as they trade away the expert trainer (I think) feature.