Tainted Grail: Conquest
40 Achievements
GOG
All Skill
Win a fight having less than 5% HP.
16.2%
How to unlock the All Skill achievement in Tainted Grail: Conquest - Definitive Guide
This will probably happen naturally, as you will be fighting an awful lot to try and earn the rest of the list. If you want to try and earn it though, the best way to do so would be to find a "Stray Monster" encounter near to the village entrance in the first area. that is not against an Infected Human. Once you have found it, almost kill your enemy and then just keep ending your turn straight away, letting it hit you down to within 5% of your max HP, then deliver the killing blow. If you are worried about not drawing a damage dealing card, you will most likely either draw enough defensive cards to survive, or have a Throwing Knife item ready, for a guaranteed kill.