Pigeon

The Volunteers (aka "pigeons") are the medics of Tooth and Tail, a Tier-1 unit which heals rather than attacks. Pigeons possess no offensive capabilities at all and instead stay at maximum range at all times, healing any non-structure unit that is not at full health. The Volunteers' med-packs heal 1 health per second for 2 seconds, and can only deliver a care package once every 2 seconds. A single unit can receive aid from up to 9 pigeons at once, allowing the healing per second to stack. Pigeons, naturally, are flying units, providing an increased visibility range and the ability to fly over cliffs and water without penalties.

Strategy
"Strategy is largely dependent on your own unit composition, your opponent's unit composition, as well as map layout and other factors. Please take these suggestions with a grain of salt."As mentioned before, pigeons are winged non-combatants and will hang back behind an army to the best of their ability to avoid getting shot down. As such they are vulnerable to any unit able to reach them.

Playing with pigeons
Pigeons are generally better off extending the lives of beefier, high value targets such as Chameleons, Boar, and Badger. The higher HP totals of these Tier-2 and Tier-3 units allow them to make better use of the pigeon's heals over a longer period of time. In extended fights, pigeons can extend the lives of your units enough to turn the tide of battle. Pigeons are also effective in skirmishes as they can heal your units in between each fight to make sure you always have healthy units for the fights, providing more mileage out of units like lizards. In addition to their medical assistance, pigeons are great for granting vision. Pigeons can ensure your opponent is unable hide on high ground and make it possible for your longer ranged units, e.g. ferrets and Fox, to acquire targets without exposing the commander to danger.

Playing against pigeons
From a numbers perspective, pigeons give a 1 DPS damage reduction to which ever unit they are healing, e.g. if you do 3 dps to a unit that's being healed by 1 pigeon, your effective dps is now 2. That being said, the damage done by each hit still goes through, i.e. you're not actually doing 2 damage per hit, but 3 damage with 1 being healed. So, the most effective way to get rid of units being healed is burst damage and killing the unit outright before it can be healed. Units such as toads, chameleons, ferrets, Badger, and Fox make pigeons heal almost negligible with their high burst damage. If you're interested in taking out the pigeons themselves, ranged units which can hit air units are the way to go.

Changelog

 * Pre-Alpha 28:
 * Vision range added to flying units is now 2, down from 4
 * Range is now 2, up from 1
 * Can now heal while moving
 * Will now stay at maximum range while healing
 * Healing packages now travel at .25 seconds, down from .5
 * Pre-Alpha 24:
 * Now heal at 1 heal per second, down from 2
 * Pre-Alpha 21:
 * Now heals at melee range
 * Heals can now stack
 * Pre-Alpha 17:
 * Hitpoints now 10 (was 5)
 * Pre-Alpha 12:
 * Cooldown now 2 seconds (was 2.5s)
 * Heal now lasts 2 seconds (was 2.5s)
 * Pre-Alpha 11:
 * This patch changed the “damage per 5 seconds” system to a “damage per second” system.Therefore, damage values have to be divided by 5 before they are comparable.
 * Now heals for 1 HP/s (was 2 HP/s)
 * Pre-Alpha 4:
 * Heal now lasts 2.5s (was 1s)
 * Now heals for 2 HP/s (was 3 HP/s)
 * Cooldown now 2.5s (was 1s)
 * Heals are now represented by a white bullet
 * Will no longer target units that already have a heal applied to them