Just how does the tank seem like a better target than the squishy mage or priest? Here are a few of my thoughts:
- Someone makes some snide remark about the boss' mother, and the computer-driven AI goes into a rage-blinded, stubborn frenzy against that person until they're dead, or someone else makes insult.
- Most impressive and threatening-looking armor: the guy attacking you with a scythe sticking out of his helmet seems like more of a threat than the little gnome standing in the corner in an evening gown. Among healers, apparently walking trees are just too scary compared to people, though the armor of the shaman and all their shiny totems also seems to increase their threatening appearance. As for the armor of paladins... well, I guess the bosses figure if the paladin who looks like the tank has put his shield and sword away in favor of making sparkly, sunny, holy lights, he must not be a problem compared to all the people with sharp objects.
- Alternatively, divine magic must be far less threatening than natural magic for some reason: shaman and druid threat vs priest and pally. Some of those we fight are "gods," themselves, but nature's wildness and its competition with most construction (compare emerald dream to current azeroth?) maybe make it seem more threatening? Maybe? (fear the bunnies!)
- Boss rules? Do they sign a contract stating they'll install and use Omen or KLH or an internal threat-meter, and attack whoever passes threshold? Perhaps to offset the otherwise game-unbalancing power they've been handed.
PvP content is different: if you want to taunt your enemy, you have to make them mad at you, personally. I've seen it done in PvP, though it's far less possible in the current game: the notorious lowbie-gankers, or the ones who like to corpse-camp while doing crude emotes, or even the leaders of strong guilds on the server during realm-wide opening events such as the AQ40 chain when they decide to wait to turn in the quest for whatever reason while the rest of the server is screaming at them to finish so everyone can begin raiding the dungeon. At that point, the player's name becomes a kill target to many enemies they may meet in PvP combat, which can effectively make them a tank. Since the introduction of cross-realm BGs, however, this is far less possible, as the swarm of people and servers brings with it anonymity.
As players in PvP can make their own decisions about what is most threatening, often these things are considerations:
- Armor: the mage is squishier than the shield-bearing warrior. The mage wearing what looks like greens is squishier than the one with the graphic art of the most cutting-edge content or resilience kit. Some gear is also a dead give-away on the player's role as a healer: the old vanilla-wow Benediction staff was refered to in pvp as the "Kill Stick" for this very reason, as it was a big glowy "hey I'mma healer, come kill me!" symbol.
- Proximity: the guy next to you is a far easier and more threatening target than some guy across the map.
- Aggro: the guy stabbing you is more threatening than the guy that's stabbing someone else... unless that someone else is your healer. Aggro on your buddies can even carry you across a map as you rush to defend a node or flag.
- Injuries: if you can take out a guy quick (and maybe earn a killing blow) while weakening their forces by one for a short time as they wait to res, they're a more worthy target than some other guy at full health.
- Specialists: healers will make it far more difficult to bring down anyone else; someone who is spell-locking or interrupting your buddies may also be a higher priority than those who are not. Also, the flag-carrier must die, or the guy trying to cap your node.
These guys have some of the most realistic AI threat in the game, which is why so many PvE guilds stumble over them: they are different from PvE threat, but still have rules compared to PvP. The guide on their threat at maintankadin has been linked around a lot recently, but for posterity, I will link it again.
The Faction Champions decide their threat on the following factors (among possible other things):
- Proximity: someone closer is more noticeable and a more immediate threat, thus their actions will seem more threatening. Afterall, someone far away may not even be in range to cast at them, so they are not as threatening.
- Armor: someone who looks squishier generally is squishier. You can cut down a mage far faster than a walking Mecha in full plate. Even pugs use this rule when considering kill orders in instances against enemies. To quote BBB, "When in doubt, we shall kill the casters first, for they are squishy and taste good with ketchup."
- Injuries: someone bleeding is a lot closer to being taken out, usually, than someone without a scratch, especially when considered by relative percentage of injuries. In a game where someone who is barely standing can still hit you with a 15k ball of fire, you may as well take them out before you begin working on the guy who's pristine, especially when there is a risk that they will be healed up shortly.