Question: Healing

[Nobukado]

Do units naturally heal over time, and if so, when do they start healing (i.e. do they need to be inside a building or something? do they need to not move for a turn?), and how much HP is restored per turn?

The manual doesn't make this clear.

[breadfan]

Unit do heal over time:
- heal when unit is moving overland
- heal when standing still (though I may be wrong on this one)
- heal when inside any of the buildings

As to for how much they heal, it should be reflected in unit stats, as far as I remember.
If you don't see the healing stat then be sure to use the community patch, it makes more stats available for the player to examine.

[GreyHuntr]

They heal in general, but they heal more if they end the turn inside a building.

[Fey-Yell]

It also depends on Faith. Life units, generally the weakest (aside from their archers), have the best natural healing of any Faith (in addition to their plethora of healing spells).

Death, ummm. Let's just say, Death believes you shouldn't really heal up, Just buy them new again. Undead, doubly so, as theirs is 0. Even the Lich doesn't naturally heal (It regains life via stealing it from others, like the Vampire).
Edit: Mantera strongly implies there's a recovery difference, with moved always being 1 (or 0, in the case of Necromancer and Bat). My bad.

Chaos, as I recall, are the only ones that recover best when they move.

[Nobukado]

Thanks.

[Meogron]

Least healing when unit moves. Unit heals more when it doesn't move. Most healing when it's inside and doesn't move.

[Heau]

Mantera mod UI changes exposes the healing parameters. It changes the game a lot so I'm not necessarily recommending it, just saying that it helps piece together hidden mechanics.

Under the hood every unit has 3 parameter value for healing. One for movement, one for overland stay and one for building stay (including in a cleared cave). Off the top of my head, that number is multiplied by the current number of units in the pack so like using a healing skill to push a low hp 3-unit from 1 surviving unit to 2 surviving units in display can speed recovery a lot.

And yeah it tends to vary sharply by faith, unit tier, hero, etc. with life healing the most passively and some death units having as little as 0/0/0 (can only heal with spells or a temple).