- Character Tiers: Enforced due to different species having different likelihoods of attaining sentience. Robots are the most likely if introduced. Below them are mammals and dinosaurs, the most likely sentient species to occur by laissez-faire play. At the bottom are Trichordates, which even The Monolith will frequently fail when used on, and below even that are Carniferns, which not only need specific conditions to appear in the first place, they are very difficult to control enough to develop intelligence before another species beats them to it. Still, though, sentient carniferns.
- Crowning Moment of Funny: What's the one thing that can halt a robot infestation singlehandedly? Daisies.
- Fridge Logic: Traveling sentients can be seen riding horses or horse drawn carts, even if mammals do not exist on the planet.
- Game Breaker: The Monolith, which allows you to choose a sentient species rather than wait for evolution. Risky in scenario levels due to the high energy cost, but not in modes where energy isn't a factor.
- Nightmare Fuel:
- It's possible (and common, if the monolith is used too early) for intelligent life to completely die out. If this happens, you will be notified that civilization has collapsed and, to rub salt in the wound, the planet reverts to the evolutionary timescale speed.
- Just how easy it is for the Nigh Invulnerable robots to take over when even one is introduced. Unless you're intentionally trying to unleash them, seeing your carefully built up biosphere being wiped and cornered, robotic tiles becoming more and more common, can be fairly distressing.
- Porting Disaster: The Virtual Console port of the Turbo-Grafx 16 version works fine for the most part, but the Save Game Limits due to the nonexistence of the file cabinet can be rather annoying.