Climb and Mount

Climbing on Creatures is possible, provided you have Climb movement. You simply spend 1 Climb Movement per Square (5ft) of their Height. You can Cling to the Flank of a Creature if you end your Climb Movement on their side.

Alternatively, you can position yourself on top of the Creature to enter the Mounting State. A Creature who has another Creature on top of them is considered in the Mounted State.

Mount Creatures

When Mounting a creature, you can use your Mount Proficiency abilities to attempt to control the creature's Movement on your Round with the Lead Tactical Maneuver. For Friendly creatures, this Maneuver always succeeds, but for Hostile creatures, this Maneuver is Disadvantaged.

Alternatively, you can Cling to the side of a Creature if you wish to attack their Flank. This can be a very risky, but awesome, way of staying in melee range of Creatures that can Fly, like dragons and griffins, but be careful of Falling off!

Some Creatures have vulnerable Weak Spots on their body that can guarantee Critical Hits if successfully Attacked! Proficiency in Knowledge, Survival, or Perception can help identify Weak Points, and your Game Master will tell you about them.