Vampires are not uncommon in The Elder Scrolls series. They play a large role in quests in Oblivion and Skyrim. This is not any different from The Elder Scrolls Online.
In ESO (or TESO) vampirism can both be a burden and blessing. Being a vampire in ESO does not affect the story in any way. It functions as an extra skill tree within the skills system. It features powerful passives and access to two active abilities and an ultimate ability.
Vampirism in ESO has four different stages increasing the severity of the negative effects of the disease, but also decreases costs of the abilities. This progress to the last stage (stage 4) happens over time. A vampire can feed to reduce the severity of the disease.
In ESO there are two ways to contract vampirism:
The first method is fighting NPC vampires. There is a small chance of becoming infected. This change supposedly is higher during full moon.
The second method is to be bitten by a player who is a vampire. This player has to unlock the 'Blood Ritual' passive before being able to. A player can only bite another player every 7 days.
You can find vampire shire (altar) locations on our Vampirism page.
Undead cannot be killed, can they? Vampires are powerful and in The Elder Scrolls Online there is a reason for it. Their passive, active and ultimate abilities are very beneficial for magicka builds in certain situations.
The ultimate ability: Bat Swarm and it's morphs increases survivability significantly. Especially the Devouring Swarm morph offers AOE damage and self-healing. Often tanky builds use this ability to have some time to breath and recover resources.
Drain Essence is a special ability. Its morph Invigorating Drain is the only magicka ability that actively grants ultimate to the caster. It also is a stun and self-heal.
Mist Form offers vampires a cleanse of all negative effects, but also increases movability on the field. It reduces damage taken by a stunning 75%. The trade-off is no magicka recovery and the caster cannot activate any ability while it is active.
The passive abilities grant the player with more stamina and magicka recovery, reduced damage taken while under 30% up to 33% and ignore movement speed penatly while in sneak.
Vampires do not like daylight, and fire. The benefits of being a vampire do not come without cost. The severity of the disease becomes more significant every stage. Health recovery plummets and the damage taken from fire goes through the roof.
A vampire has 75% less health recovery, although the Unnatural Resistance passive reduces that amount a little. The increased fire damage taken (up to 25% more) is a real pain in dungeons where a lot of fire damage is pressence (e.g. Bloodroot Forge and City of Ash).
Another threath vampires encounter is the fact that they are Undead. The Fighters Guild skills and passives deal a massive amount of damage to Undead. Fighters Guild abilities can deal up to 20% additional damage to Undead enemies.
It heavily depends on the situation. If you are going to do PVP, vampirism can be very beneficial. The pros do outweigh the cons in my personal experience. In PVE however this is very different. There is a lot of fire damage in dungeons and trials. If you decide to go vampire in PVE anyway, the best stage is stage 2. At that stage you will get all the benefits but less severe negative effects.