Rabies
you can face aliens in the "mothership zeta" expansion and as for zombies the closest thing to them is the feral ghouls which are practically zombies.
hey the closest one to nazi zombies that i have found is called SAS zombie assault
Left 4 dead.
There are a few different types of zombies. The original would be Voodoo/Voudo based zombies that are corpses conjured to rise and to the bidding of the person that called upon them. Medical/Government zombies, which are zombies that have been reanimated due to chemical or bio experiments. and Sickness Zombies, which are zombies that became that way due to evolving viruses in humans that turn the host into a mindless flesh/brain-craving undead maniac.
Mini Robot Wars is the closest thing to PvZ.
Because they carry viruses, also they like eating humans. So if a zombie touches or bites you then you could get infected or turn into one...
Left 4 Dead 2 and 1. Also, Resident Evil 5. Also, Deadrising is pretty good from what I have heard.
There are no zombies. Zombies are fiction.
they are the leaders of zombies and strong zombies
By surviving and not dying you can make the levels continue longer, but you will finally die and lose. It is a survival type game where staying alive for longer is the closest you can come to winning. You never beat the game in zombies mode, it was not designed to be ever beaten and instead was designed to never be beaten
No! It shouldn't be. Plants Vs. Zombies should be clean, playable and safe. If you have a minor lag after playing it, then it must have a Malware. Be sure that the copy of Plants vs. Zombies you have is 100% original. Some crackers just cracked the game using bots and other files. This can leave an imprint to one of the game files. Sometimes, the virus will hangout in the "bass.dll" file in the main directory of Plants Vs. Zombies. You must download and install a clean copy of the game to resolve this.
The closest answer is parasitic since certain viruses harm the host cell in order to replicate and survive (not all viruses do, though). Chemosynthetic and photosynthetic would imply that viruses themselves contain the necessary biological machinery to carry out cellular functions, which they don't.