Lesser green mutagen is an alchemy ingredient and is be used to craft Green mutagens and Reliever's decoctions. They can also be used to augment abilities, but are not as effective as their regular or greater counterparts. When placed in the diamond-shaped slot in the character panel, they give +50 to vitality, which increases by 50 up to a max of +200 if all 3 skills attached to it are green.
Blood and Wine expansion
With Blood and Wine, the player can now craft these with other ingredients.