If dweller reach some age they will die or retire from vault peacefully. In-game age can be fixed period like weeks or a month, Or some fixed level, or playing time, or combination of these.
Of course , death by age alone won't solve the endgame problem. But the lack of death by age is making problem worse.
And death by age itself in casual game has many potential problems like emotion. Retirement msy be less problematic.
I'd like to hear your opinion.
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