The Sims 4

Age Extension and Immortality

Drinking the Essence of Life from a Cow Plant will reset your Sim back to day 1 of their current life stage. Potions of Youth do the same, costing 1500 Satisfaction.

There are a few ways to make your Sim live forever in The Sims 4. Some involve cheats, while others do not. Let's explore some of the means of life-extension in the game, and what we can do to make that a regular part of the Sim's life.

Non-Cheating

Age Settings
Know that there are aging settings in The Sims 4's gameplay options menu. You can select whether all Sims age, or only those in your household, or disable aging entirely. Setting the Life Span to long will make children and teens take quite some time to age up, but you'll have loads of time to accumulate satisfaction for the following reward.

Potion of Youth
The Potion of Youth Reward is the easiest means of keeping a Sim youthful without cheating. The potion only gives one drink, but will reset the Sim back to the beginning of their current age group. Use it right before they age up for maximum value. Simply accrue 1,500 Satisfaction points by pursuing Whims and your Sim's Aspiration. and purchase this. You can even transfer these between Sims. This is my main go-to for keeping Sims young. However, there are other a couple of other options.

Cow Plant
When a cow plant kills a Sim, they give an essence of life that can be drank, offering the same benefit as a Potion of Youth. But a Sim must be killed. Don't feed the cow plant, and have them in a place guests will mingle or else have one of your own Sims take the cake it puts out as bait when hungry. Do this once, the Sim gets a negative moodlet. Do it a second time, and the Sim dies and leaves behind the essence, which is available when you milk it. You can learn more about Cow Plants in the Gardening Guide.

Get to Work - Scientist and Cloning Machine
Scientists can make the Age-Away serum, which will reset a Sim's age back to day 1 just as the other options do. It also is rather easy to get, though you've got to be level 10 in the Career. Additionally, the Scientist Career gets access to the cloning machine which can be used to make copies of potions, such as Age Away and Potion of Youth, and even Ambrosia or its ingredients. There are other great benefits to this Career, so I highly recommend it.

Cheating

Free Potion of Youth
Multiple routes to a free Potion of Youth. You can cheat to give your Sim points by using sims.give_satisfaction_points 1500 (or more) with testingcheats on. Additionally, you can use bb.showhiddenobjects to be able to find potions of youth for $0 in buy mode (use the search function).

Make Sim a Ghost
This requires a cosmetic change, given your Sim will be transparent. Look to our Ghosts Guide for cheats to make your Sim a type of ghost and take on the side effect of immortality. They won't age, and can't die!

Edit in CAS
Apparently, at time of writing, using the cas.fulleditmode cheat along with testingcheats to set your Sim back in age will result in them losing all their reward traits, while aspirations stay completed. This is no good, as you'd have to cheat to add them back in given the inability to redo the aspiration. Just use the points cheat above for this!

Prevent Death

With all this stated, Death can still take you (unless you're a Ghost). The solution to this is to have a Sim who has Death Flowers (Graft Orchid with Pomegranate) in their inventory to protect the other Sim from death by giving them to Grim on his visit. Additionally, Sims with high level Mischief can toy with death to perhaps prevent a Sim from dying, Sims can plead, and this works better when they're Confident.

Mods

Eternal and Immortal Buyable Traits
Created by vitopiresa at modthesims.info, you can buy the two listed traits for 6,000 and 8,000 satisfaction each. These are permanent. Eternal stops a Sim from aging, while Immortal will prevent a Sim being taken from the reaper. You can Download the Mod Here.

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