What bonuses do they give?

看到你发布。我还是删除吧，龙凤MOD，攻打龙不掉龙玉，我想是因为原版龙就是没有龙玉，MOD没有覆盖原版的龙。。

Thank you very much,reinstall helped :D

Sorry for late respond but are you sure install mod correctly?
I'm pretty sure that these alway auto unlock when mod active

For anyone still wonder how to craft these spirit contract:
1. Build "Crafting Table"
2. Have atleast 1 Inner Xiandao Cultivator
3. Choose the Inner and F4 and choose "Legacy Artifact"
It will alway unlock if it on new game then these will be on the first 2 slot formula

do you have to defeat all free before unlock?cause i dont have the formula

It auto unlock Formula
And you can see by yourself ingame

whats the material or where do i get the recipe?

You can craft it like the Artifact Treasure or Relic in Artifact Craft Pedestal

how to craft them?