2/2
The game's been getting constant updates for over two years, user, I'm pretty sure it's been improved. I find combat pretty solid.
STEALTH
Hit ctrl to crouch and sneak around. This can be used to evade zombies or to land a double damage sneak attack. It's more trouble than it's worth to try to land stealthed melee, so you'll primarily be using this for your opening bow/crossbow shot. A stealthed bowshot will oneshot lighter zombies with a bow of decent quality; with a good crossbow, all but the biggest guys (infected cops/feral zombies) go down.
MELEE
Ammo is conserved but you place yourself in danger of being hit by a zombie, which can:
BLEED - Health ticks down til death unless you apply bandage. Bandages are stupidly easy to craft, you just want to be sure to get out of range and apply them ASAP.
STUN - Vision blur and slowed movement for several seconds. This is probably the worst to suffer, since you'll probably be hit at least once more by the zombie who inflicted it and it lets any other zombies close in on you.
INFECT - Being hit by a zombie carries risk of getting zombAIDS. This is easily cured by consuming honey, tea (stage one; treat within 2-3 IRL hours) or antibiotics (stage 1-3), all of which you should come across soon enough while looting. Easy enough to deal with, but it's another risk to melee.
Melee is ideally reserved for individual or loosely-grouped zombies in daytime, and performed by darting in, landing a headshot and darting out before the retaliatory swipe hits. Enough head trauma, whether from melee or ranged, knocks a zombie down for a few seconds, which is a good opportunity to wail on its head with melee.
RANGED
The safest method that becomes more viable as you progress. Starting with a bow, then crossbow or lighter firearms as you find them, you can drop zombies from a safe distance at the expense of ammo.
BOWS/CROSSBOWS - Easy to produce and easy to resupply. Feathers from birds nests/wild chickens are the only "difficult" resource in arrow/bolt-crafting, but 10 minutes of nest-hunting should get you the feathers for at least 50 rounds. Both weapons are silent and stealth-friendly, unlike firearms. Even in endgame, you'll want a crossbow on you to conserve ammunition.
GUNS - Pistols, shotguns, sawn-offs, hunting rifles, SMGs, AKs and rocket launchers. Guns are assembled with four core components (stock, receiver, barrel and parts) that cannot be crafted, only looted. Pistols can be found rarely in most containers, low-end guns in gun safes/gun stores, high-end guns in gun stores, treasure chests and airdrops.
Guns have two forms of upkeep, durability and ammo. They can only be repaired with repair kits, which use a variety of mildly uncommon looted materials to craft. Any prolific looter can produce more than enough.
Ammo can be looted, but not nearly in large enough quantity to sustain frequent firearms use. Ammo creation costs lead (bullet tips), gunpowder (nitrate + coal) and brass (shell casings). Lead is salvaged from loot or mined, with some effort. Gunpowder's components are mined quite easily, as surface deposits now spawn fairly frequently. Brass is obtainable only via looting. Lead and brass must be smelted down and then forged into components. The only exception (besides rocket launchers, unfamiliar with those) is default shotgun pellet ammo, which uses lead, paper (lootable en masse) and gunpowder. If you get a good lead mining setup going, the lack of brass in shotgun ammo allows you to produce ammo without depleting valuable brass stores, so long as you have the paper.
Guns are, naturally, the most powerful weapons. They're also the loudest, and each round fired produces 0.3% "heat" (minus the SMG, which produces 0.1%). "Heat" is a metric used to represent the general ruckus you produce, and also goes up with use of tools or forges/campfires. At 100% heat, a type of scout zombie will spawn and come along to investigate, spawning a horde if you don't put it down before it spots you.
EXPLOSIVES: There are also TNT and mines. I'm not very familiar with them since they never seemed efficient enough to use in PvE, but I'm sure they're hilarious in PvP.
