Catahecassa

Size: Large 
Hit Dice: 7d8+21 (52 Hit Points)
Initiative: + 1 (+1 Dex)
Speed: 40 feet
AC: 16 (-1 Size, +1 Dex, +6 Natural)
Attacks: Gore +12 melee (2d6+10)
Face/Reach: 5 feet by 10 feet / 5 feet
Special Attacks: Trample
Special Qualities: Scent
Saves: Fort +8, Ref +6,Will +2
Skills: Listen +7, Spot +7
Abilities: Str 25, Dex 12, Con 16, Int 2, Wis 10, Cha 6
Tricks: attack, come, defend, down, guard, heel, track, work

Feats:

Alertness: +2 bonus on all Listen checks and Spot checks

Endurance: +4 on Swim checks made to resist nonlethal damage,
Constitution checks made to continue running, Constitution checks 
made to avoid nonlethal damage from a forced march, 
Constitution checks made to hold your breath, 
Constitution checks made to avoid nonlethal damage from 
starvation or thirst, Fortitude saves made to
avoid nonlethal damage from hot or cold environments, 
and Fortitude saves made to resist damage from
suffocation. Also, you may sleep in light or medium armor without becoming 
fatigued. 

Trample (Ex): A riding bison can, as a Full Action
each turn, run over an opponent that is of Medium Size or smaller,
dealing 2d8+8 points of damage. A Reflex Save at DC 20
halves the damage. Trampled creatures may forego
the Saving Throw to make an Attack of Opportunity
on the riding bison but suffer a -4 penalty on the attack roll.

Link (Ex): A druid can handle her animal companion as a free
action, or push it as a move action, even if she doesn’t have 
any ranks in the Handle Animal skill. The druid gains a +4
circumstance bonus on all wild empathy checks and Handle Animal
checks made regarding an animal companion. 

Share Spells (Ex): At the druid’s option, she may have any spell
(but not any spell-like ability) she casts upon herself also 
affect her animal companion. The animal companion must be within
5 feet of her at the time of casting to receive the benefit.
If the spell or effect has a duration other than instantaneous,
it stops affecting the animal companion if the companion moves 
farther than 5 feet away and will not affect the animal again,
even if it returns to the druid before the duration expires.
Additionally, the druid may cast a spell with a target of
“You” on her animal companion (as a touch range spell) instead of on 
herself. A druid and her animal companion can share spells
even if the spells normally do not affect creatures of the companion’s 
type (animal).

Evasion (Ex): If an animal companion is subjected to an attack
that normally allows a Reflex saving throw for half damage, it 
takes no damage if it makes a successful saving throw.

Improved Natural Attack: Choose one of the creature’s natural
attack forms. The damage for this natural weapon increases by one 
step, as if the creature’s size had increased by one category.