If you level up a conclave and get the 'scroll scribe' build the apothecary, you can buy a potion in the shop that removes injuries.

Edit: Yeah, Heavenfall clearly knows better

For the record, did a little testing. Apothecary makes three potions available:

Healing Potion - 100 gildar - heals 60 hit points

Growth Potion - 115 gildar - buffs for +50% attack, -20 dodge (just for one battle)

Iru Elixir - 150 gildar - heals 100, removes one random injury

Scroll scribe gives you:

Blizzard Scroll - 90 gildar - Tactical damage spell with a 2 tile radius, does 8 (+2 per water shard) cold damage per member of each enemy unit

Air Elemental Scroll - 135 gildar - Summons Air Elemental for one battle. (Doesn't quite have the same stats listed in Hiergamenon. Level 5, 4 moves, 21 attack, 0 def, 55 hit points, 28 init, 80 accuracy, 9 dodge, casts Titan's Breath).

Oh...

Well I feel stupid now. I do find this solution a bit intricate, but I sure won't protest.

Thanks!

I just wish the computer would take advantage of it since they get some really beat up heroes at times. Either that or auto resolve should be kinder towards heroes, or maybe make auto resolve simply not take account of severely wounded troops in exchange for not killing them

The ability to remove the injuries has made Champions even more powerful than they already were.  Plus all of them having magic, and now they are never injured---the game is eliminating the need to even make units.