I’ve been playing with hordes since they came out last year.
Personally I use hordes specifically for taking down Military Outposts. If you draw a horde to an outpost, the turrets will use all of their ammo on the horde and take a ridiculous number of hits from zombies and basically aggro enough of the horde that you can get in and get out of the outpost without any real difficulty. Military Outpost = military ID cards = opening up Military Bunkers = the best loot in the game.
Other than that, the main tips I can give you are:
- Be quiet
Guns are still useful, but I almost never use shotguns unless I want to draw a horde. Suppressors work outside of cities, but for some reason using any gun other than a super quiet .22 will cause the zombies in the city to aggro on you, even with a suppressor.
- Always have a working vehicle
Vehicles are basically the only way to get out of large hordes that spawn on your position. It helps to have an armored vehicle to plow through, but if your driving skill is high enough and you are in an open area, you can still get out reasonably easily.
- Don’t let hordes spawn
Just because a horde shows up on the overmap doesn’t mean that there are any zombies there. The horde gets spawned when the player character comes into contact with the horde, which basically just floods a random number of zombies when the player is about 1-2 map tiles away from the horde.
Always drive away from hordes. You can come back later once the horde is gone, and there shouldn’t be any horde-generated zombies there, even though there was before. As long as you don’t see the horde, it isn’t there. The Zs on the overmap that represent hordes are just potential spawns, not actual hostile zombies.