Dogs will be the 1st monster you will come across in Penumbra: Overture. These feral beasts will start to attack Phillip as soon as they spot him, but have bad vision if hiding. There is a way to kill these beasts. Either run up on one and try to take it down or gain some height to where they cant hit you while you can hit them! If your not a fighter you can acquire some beef jerky that can be used to distract the dog for a couple of seconds. Dogs are much faster than Phillip so don't try to outrun it. You will most likely die. The best way to escape these beasts is to either fight back or get somewhere the dog can't get to. Dogs can also push open doors that go inward, meaning they can reach Phillip if hes in the room. Best way to counter this is to block the doors with whatever you can find and then run to a hiding spot because he will break through soon enough and will be wandering that room. Depending on the difficulty you play on these dogs will be more of a hazard or a tough fight, even on the easiest mode these guys are a challenge. Another form of distraction is to use flares, they will follow them so put them in a corner or in its view. Also when a dog is hit with a Pickaxe it will instantly fall to the ground, then upon standing back up will temporally run away and call other dogs to aid.

Worms are living around the mine and the shelter. Although pretty easy to escape from these kill Phillip on contact and should be ran from. You only encounter them in scripted events so no need to worry about them just sluggin' around the game!

Spiders are 1st encountered in the tunnel system above the excavation tunnel. They are weaker than dogs but usually are a lot in a pack. Spiders hate light so using your flashlight on them will make them retreat for a short time. The glow stick does not give this benefit so its good to have your flashlight charged for these guys. There are huge nests of them in Shaft 13 but can be avoided if you block off the tunnel once you reach the locker room. They have good vision and will find Phillip even when hidden. With most weapons spiders will die with 2 hits, but can be difficult to kill when there are more than 2 at a time.

Hope this brief summary of the enemies helped you in fighting them or avoiding them!