Tainted Grail: Conquest

TL;DR
Find Bard 3 times
Find Honir's Spear from encounter with a merchant
Find Bard again
Find Bard again and choose to look for Honir
Talk to Ghost
Talk to Bard and offer him a place in the village

The Bard is the most difficult NPC to recruit for your village, as getting his dialogue option to join requires completing a two part quest. To start the first part, you have to find the Bard 3 times throughout your runs and talk to him, which he will offer you the ability to pick card or remove 1 from the deck. On the 3rd time, he will give you dialogue about finding his brother and start A World Fixed in Evil Part 1. To complete this, you need to find the item Honir's Spear, which we will be found randomly on the map in an encounter with one of the traders. Once you have it, you will need to find the Bard again to give it to him and that will finish the first part of the quest.

Finding him again will allow you to start the second part of the quest. DO NOT CHOOSE THE SONG OF FORGETTING. It will NOT allow you to recruit him, and this change is PERMANENT. Once you have chosen to look for Honir, talk to the Ghost next time you are in the village. Then find the Bard one last time and talk to him, going through the dialogue until you can recruit him. Once you choose the option, the achievement should pop.