- Starting with the Director's Cut version of Resident Evil, Forest springs back to life to attack the player. In REmake, a mode is added called One Dangerous Zombie where he is covered with grenades, making attacking him suicidal.
- The REmake features one unique zombie on a return trip through the graveyard late in the game. It's similar to the overweight, balding zombies seen in the mansion, except this one has no hair at all and wears only a pair of white boxers. No other zombies anywhere else in the game share this character model.note
- Only one Sweeper appears in the REmake, in the Kenneth Room on the return to the Mansion. Unlike the ones in Code Veronica, however, it can not poison you.
- There is only one giant moth in the entirety of Resident Evil 2, in an optional out-of-the-way room in the lab basement. Screenshots of the beta (not RE 1.5) showed more of them in other locations, such as the power room. There are also only two rooms where players encounter mutated cockroaches.
- In Resident Evil 3: Nemesis, you're only guaranteed to run into two of the Gamma-type Hunters (the frog-like ones). There's a 50/50 chance of encountering two more on a walkway in the park.
- Resident Evil Code: Veronica has the poison moths in that one corridor, which you unfortunately have to traverse multiple times. When you revisit the area as Chris, they're gone, replaced by zombies. Some of the zombies do show what happens if the moth eggs are allowed to hatch and grow, as a parasite of some kind will launch itself out of them in a couple of places. Earlier, in the passage to the seaplane port, several of the men comprising Wesker's private army can be found in zombie form. They're mostly notable for the light coming off their night vision goggles and tendency to explode when shot. Finally, Claire only has to deal with the baby albinoids for all of 5 seconds.
- Resident Evil 0 has the Lurkers, of which you are only guaranteed to run into once.
- Resident Evil 4:
- Among the game's already rare Garradors (a total of four), there is only one Heavy Armored Garrador.
- The Armaduras (not to be confused with the armor suits that strike once, then collapse) only appear in two rooms of the Castle.
- Novistadors normally are either invisible or airborne, but not both; however, there is a lone invisible flying individual in the Nest Tower; after you kill it, it's gone forever. Another unique variant is completely white with black eyes.
- The three Iron Maiden Regeneradors in Chapter 5-2.
- Also in Chapter 5-2 is Oven Man.
Unique Enemy / Resident Evil