Zombi is the oldest zombie surival horror game that I have played. Similar to left for dead, you start your game on top of a building, after (what seems) your helicopter has broken down. You play as a squad of 4 surivors, each having their own stats.

You have you move your squad, per person, through the areas of a mall. Locations are traversed by exiting screens left/right/forward or backward. Items are found on locations and can probably be used on other items.

Zombies are wandering around, and the game gives you a little time to move away until the zombie attacks you. A few situations result in sudden death (like wandering too far outside the mall). The aim of the game is not entirely clear to me, but it seems like you have to get your chopper going again.