There is a mod for Half Life called Zombie Edition. It is rather short for my liking, but it is a good mod. You play as a headcrab and can mutate into different zombies with different abilities.
2:00 Necro: "Not the Falling In Reverse 'Zombified' but-" Me, hearing the band name, and knowing a true anthem: 🎵"It's just a GAME, that we PLAY, and for Heaven's sakes! Looking for a better way to play it! Life is for, Keeping SCORE, and forevermore. STOP COMPLAINING and Start CHANGING IT!"🎵
Shame thet u canot throw Head crap and veest to get health and not dropping just like in half life 1zm there is a Zm mod u can play and throw the Head crabs to other hamans to zombine them as well and not health droping it's fun to se this player model been use in sted siting Ded in the canals level and other places in half life 2overall1/4