Blood Hawk

A blood hawk on the party's side is a ranger's companion, a scout's trained bird, a druid's recurring wild shape target, or one bird inside a falconer NPC's mews who agrees to lend it for a job. The framing has to acknowledge that this is a beast with no real attack on the sheet: the bird is a tool for reach, not a damage dealer. Anyone who tries to send it into a fight against humanoid adversaries is going to lose it.

What the bird is good at is the 60 ft. fly speed and passive 16 Perception. Send it ahead to spot a campsite, count the bandits behind a ridge, watch a balcony for movement, or carry a small message tied to its leg. A ranger can use the Beast Master rules (or DM equivalent) to issue commands, but even as a non-companion the bird responds to whistled signals if it's been trained. Treat reports as visual impressions: number of figures, presence of light, whether anything is moving.

The bird refuses cages, refuses smoke, and refuses any space it can't take off from. If the players try to stuff it into a sack for a stealth mission, it shrieks and bites. If they want it inside a building, the bird needs a window. Lose it once to bad handling and let the players feel the absence the next time they wish they had eyes overhead.

Give the bird a name and a single clear signal it answers to. A whistle, a wrist-flick, a piece of dried meat held up at arm's length. Players who train themselves on a one-cue interaction will use the bird more, and the bird will be in more scenes.

A blood hawk is a swarm-shaped problem with a single statline. It has 7 HP, AC 12, no listed actions and no listed traits, which means the SRD entry is the carcass of an older stat block; you should run it as a beast that uses the Attack action with a beak and treat anything else (mob bonuses, dive attacks) as DM call. The interesting fact is the speed line: 60 ft. fly against 10 ft. walk. This thing exists in the air or it dies on the ground.

Use blood hawks in flocks. One bird is a curiosity. Six are a pacing problem for a level 2 party crossing a canyon, and twelve are a real fight if the party can't generate area damage. They have Perception +6 with passive 16, so they spot the party before the party spots them. Open with a high circle, then a dive on the squishiest target. A failed Perception check from the marching order means the cleric or wizard takes the first hit at advantage from above (DM ruling). After contact, fight in the air. Anyone the bird grapples or harasses has to either ready a bow shot or accept that melee attacks are wasted on a target that flies away each turn.

Their panic trigger is loud and immediate. Blood hawks are 7 HP each, so a fireball or any cone is a slaughter. Once half the flock is down, the survivors disengage and climb. Don't have them suicide. The terror of a returning flock that learned the party's faces is worth more than a few extra deaths in the round.

Roll attack and damage for the whole flock at once with a stack of d20s, and narrate the wave. Players feel a hawk attack one at a time as paperwork. They feel six at once as weather.