Pteranodon

A pteranodon as ally is a primal scene: a druid's wild shape, a ranger's beast companion via homebrew, a dinosaur-rider tribe loaning a mount. It tolerates the rider because the rider has trained it to.

In the air, run the pteranodon as transport. 60-foot fly speed lets it cross a ravine in two rounds, scout a valley between sessions, or carry one Medium PC on a dramatic crossing. It has 13 HP, so it cannot soak archery from below. If the party flies it over a hostile camp, somebody will roll a longbow attack and the pteranodon will fall.

In combat the pteranodon is not a combat asset. It is a positioning tool. Use it to drop a rogue onto a tower roof, snatch a dropped item out of a chasm, or carry a message faster than a horse. Its 10-foot walk means it never fights on the ground. If a fight breaks out near the landing pad, it launches and circles until called back.

A wild pteranodon kept as a mount has a recall range of about a mile and a memory of about a week.

Have the pteranodon scream once, loud, when it spots a predator the party hasn't noticed. Then describe what the predator is.

A pteranodon is a flyby beast with a 60-foot fly speed and 10-foot walk. CR 1/4, 13 HP, AC 13. It has a Bite at +4 doing 1d8+2 piercing. Flyby means it doesn't provoke opportunity attacks when flying out of reach. The party kills one in two hits. The point is the swarm, the fall, or the swoop, not the stat block.

Use pteranodons as ambient pressure during a cliff climb, an airship boarding, or a jungle traverse. Run three to five at once for a level 1 to 2 party. Walk 10 feet means a pteranodon that lands is half-dead already, so they don't land. Open with a high pass: each pteranodon flies 60 feet straight at one PC using Flyby, hits with Bite at +4, then flies the rest of its movement back out of range. The party gets one round of opportunity attacks before the next pass.

The encounter's real teeth are the surroundings. A failed concentration save while a wizard is hovering on Fly. A failed Strength check on a rope bridge. A panicked horse bolting because the shadow passed overhead. Run pteranodons during another encounter for atmosphere, not as the main event. They make any fight harder by occupying the air.

Pteranodons are Int 2. They flee the moment one drops. The flock scatters into the canopy or cliff face and does not regroup.

Describe the dive as a shadow falling across the map before the attack roll, not after.