Sims also cannot take multiple blessings or curses at once, so if a single family has a Sim who is blessed and another who is cursed, they will not affect each other. Sims that are already blessed or cursed cannot be the target of a relic. The Remedy of the Ancients requires only a Level 1 Cooking Skill, so as long the Sim has cooked anything in their lifetime, they'll be able to handle the recipe. However, Ancient Bone Dust can be freely moved among inventories, so it can be taken from a healthy Sim and given to a cursed Sim. Healthy Sims cannot cook the Remedy of the Ancients even if they possess Ancient Bone Dust in their inventory. It's unknown whether this is by bug or by design, but the meal is unavailable for cooking unless the Sim who is cooking it is cursed. A new refined crystal may be placed within the relic to restore its power. Eventually the refined crystal will break and the relic cannot be used, but the relic itself (and any environment scores) will remain.
When get close to reaching the end of their lifespan, they will appear to crack and damaged. Relics only have a limited number of uses. The relic might do something positive or something negative, so choose your guinea pig carefully! Some relics also will help the user and hurt the target, but relics are consistent with their use no matter when they're used or who they are targeting. Its name will appear when moused over in the Sim's inventory, but its effects will be listed as "Undiscovered" until you use it once. When a relic is first assembled, you will not know what it does.
Note that some relics can only be used on self due to their specific effects. If the Sim chooses the latter, they can target anyone, not just family members. The Sim merely needs to interact with the relic and choose whether to use it on themselves or a target on the lot.
The completed relic can be placed anywhere in the house, but they are only useable from a Sim's inventory. Sims are guaranteed to succeed in relic assembly. Then interact with the completed relic and select the "Insert Crystal…" command, then select which refined crystal you wish to place in it. Simply interact with the base in the Sim's inventory and use the "Fuse With…" command, then select which relic you wish to mount in it. Once the relic, base, and refined crystal are gathered, any Sim (regardless of Skills) can assemble it. A pop-up box will ask which crystal you wish to use. When a material is found, a mid-level Archaeologist must interact with a Pop-Up Archaeology Table and select the "Refine Crystal" command. Instead they have a dramatic spiky appearance resembling the classic image of quartz. When crystals are dug up or looted from chests, they do not start off as refined. Archaeologists may have a better chance, especially if they convert a dig pile to a dig site and have a high Archaeologist dig level.
While some relics and bases may appear in minor chests, crystals only appear in the final treasure chest of Jungle Temples, and only sometimes. The base and relic can be found both in dig sites via Archaeology and in treasure chests. To create a relic, you will need three things: a relic base, a relic itself, and a refined crystal.