Dogmeat (Fallout 3)

Dogmeat is the dog companion of the Vault 101 Dweller. His name is a homage to the Dogmeat from the first Fallout and according to the developers, he's the descendant of Vault Dweller's original canine companion that died in a horrible accident involving a force field.

Dogmeat is said to possess lifelike AI and has many uses in wasteland survival. His main combat use, apart from minor damage, is distracting the character's adversary giving him/her an opportunity to establish an advantage. It has been stated several times by Bethesda that Dogmeat can also be used to fetch supplies that are very necessary in the post-apocalyptic wasteland. Another important note is that although Dogmeat can follow you to all ends of the Earth, he is mortal and can be killed in battle or even when acquiring materials in a dangerous territory. If he dies he will stay dead, obviously imitating reality.

Before the release of Fallout 3, the process of how to recruit Dogmeat had only been shown as a small clip as the Player holds something out to the wounded dog. The item is not revealed. Dogmeat was said to be found in a random encounter, which will appear in different places depending on where the player ventures to, but is meant to appear early on to help develop your bond with the dog. In the released game, Dogmeat can instead be found in the Scrapyard, south of Minefield. He is found attacking and killing several raiders, but approaches the Player peacefully and will join him if asked.

Appearances
Dogmeat, while named just like the one from Fallout (which was said to die in a military accident), is a new character that appears only in Fallout 3.

Abilities
You can send Dogmeat to search your current area for either ammo, chems, food or weapons; have him stay in his current location; heal him with stimpacks; or send him to vault 101's entrance for safety. He can die permanently and never come back so keep an eye on his health. Dogmeat can trip traps and attacks enemies even if they are strong melee fighters.

You can check Dogmeat's health by aiming at him or targetting him in VATS. This will tell you his health, though it does not seem to provide any information about severely injured limbs. Also, if you engage an enemy that Dogmeat is also attacking, it appears that Dogmeat can be wounded by your missed VATS shots (as well as missed regular shots). Save often to avoid permanent loss of pet until more is learned about how resilient Dogmeat is and how easy it is to accidently wound him when attacking another target.

Dogmeat may not be a very good companion for a stealthy killer. One, he can detect enemies in adjoining rooms or on floors above and below you just as you can with Perception. When he senses a target, he growls. While the growling does not appear to give away your position, it does make it hard for you to hear your enemies. For example, in the Museum of American History, which has several multi-story rooms that are not separated by zoning-doors, Dogmeat will growl the entire time. Two, he will initiate combat on his own, even if you are not yet detected. He can even open doors on his own to attack. This may force you to choose between letting Dogmeat fend for himself until you're ready or to engage in hasty combat, forfeiting the advantages of stealth attacks.

There is no way to make him not attack an enemy his AI is not that complex hopefully there will be a way to do that in a patch

SPOILER: Note: Dogmeat returns to the entrance of Vault 101 after the player is captured by the Enclave