I'm going to list some resources and tips for you multi boxers out there. Some of my info is stuff i've gleaned from www.dual-boxing.com (everything on software, tips, class combos).
My personal set up is:
1.) warlock / priest 2.) priest/priest 3.) druid/druid
hotkeynet is my software (free) - you'll have to learn how to write macros and figure out which cast order to use. I use one computer/monitor and have both windows minimized and set at diagonals with the main window at 75% size with 2nd window at 40% just enough to see where i'm going.
For the most part I find that classes are easier to use if you pair them up based on melee to melee and caster to caster. 1 dps /tank class with 1 (healable and rez class). I am copying that post because its something I use alot and rather not see it lost because they deleted the post.
----------COPY and pasted from dual boxing site----------------
Carebear Leveling High-Level Classes, from Best to Worst
1. Paladin: by far and away, the best carebear to have. First, he can heal, resurrect, and Cleanse. Second, Blessings are versatile buffs for whatever class he needs to support. Third, Righteous Defense can keep up to 3 mobs off of you at a time. And last, and somehow best, is a Paladin's non-offensive Judgment of Wisdom, which can help Priests, Shamen, and Hunters regain mana quickly.
2. Priest: very good support capabilities. Again, he can heal, resurrect, cure disease and magic effects, and adds the Power Word: Fortitude buff, which is very handy. As above, it is a big crutch that he will be unable to Power Word: Shield your lowbie without being in a party, but acceptable. Psychic Scream more than makes up for it, to keep mobs away from the ranged or caster lowbies. Last, don't forget that Shadow-specced Priests have Silence.
3. Druid: great support, especially for melee. A druid's heal-over-times are superior, can cure poisons and curses, and Mark of the Wild and Thorns are great buffs. He can only resurrect once every 30 minutes, though. Bear/Dire Bear form plus his Growl, Demoralizing Roar, and Challenging Roar lets him keep mobs off your lowbie very well with little damage to himself. Also, this is the first class with some form of crowd control: Hibernate works on beasts. Don't forget to use Faerie Fire for melee support, but avoid Entangling Roots as it damgages your target slightly.
4. Shaman: somewhat good. He can heal and resurrect, but not being in a party hurts since you cannot get any major benefit from his totems. Stoneclaw and Earthbind totems seem to work well, as does Purge. Water Breathing and Water Walk are good occasionally.
5. Warlock: king of the crowd control. He can't heal you, which is a big step down, but he can Fear and Seduce while you kill, so you shouldn't be taking much damage. Curse of Tongues, Weakness, Exhaustion, and Elements all do not damage the target, and will not be downranked, so fire away.
6. Warrior: slap on Defensive Stance, and get ready to taunt. Battle and Commanding Shouts require a party, so literally the best thing you can do is keep the mob off your lowbie. Use Bloodrage then Taunt, Demoralizing Shout, and Challenging Shout. Hamstring works to keep them in range, but make sure you don't damage them.
7. Mage: starting to get pretty bad. Mages can Polymorph, summon food and water, and buff Intellect, but after that almost all of their abilities affect themselves or damage their targets. Avoid Frost Nova for the latter reason.
8. Hunter: no buffs. Freezing Trap and Improved Hunter's Mark are the only things worthwhile here.
9. Rogue: Sap only.
Team Leveling Combinations
What you're looking to avoid here is one toon who needs to stay at range, most notably hunters, and one who needs to be up close.
* Druid/Druid: one bear, one cat, no problems.
* Druid/Hunter: pet tanks, cat and ranged dps.
* Druid/Mage: bear tanks, mage dps but not enough to pull agro.
* Druid/Paladin: ret pally tanks, cat dps.
* Druid/Priest: shadow priest will pull agro no matter what, so keep it flayed during cat dps.
* Druid/Rogue: cat and rogue stunlock for the win; use Cheap Shot -> Pounce -> Kidney Shot.
* Druid/Shaman: try grace of air and strength of earth for hot cat dps.
* Druid/Warlock: voidwalker tanks, dot dot dot, cat dps.
* Druid/Warrior: fury war tanks, cat dps.
* Hunter/Hunter: use dps pets and go all out, nothing will ever reach your hunters' melee range.
* Hunter/Mage: pet tanks, both dps.
* Hunter/Paladin: do not use.
* Hunter/Priest: keep it flayed or feared, with a dps pet.
* Hunter/Rogue: do not use.
* Hunter/Shaman: unless you can stomach the elemental tree and stay at range, do not use.
* Hunter/Warlock: voidwalker tanks, dot dot dot, ranged dps.
* Hunter/Warrior: do not use.
* Mage/Mage: try to vary your builds for double debuffs.
* Mage/Paladin: difficult, but let your ret pally get a little agro before your mage attacks.
* Mage/Priest: deadly combination; keep it flayed or feared.
* Mage/Rogue: keep it stunlocked while spamming frostbolt.
* Mage/Shaman: difficult, but let your shaman build a little agro before your mage attacks.
* Mage/Warlock: deadly combination; voidwalker tanks, dot dot dot, spam frostbolts.
* Mage/Warrior: use defensive stance if you have trouble holding agro, but berserker should be fine.
* Paladin/Paladin: are you retarded?
* Paladin/Priest: try to keep the ret pally tanking, keep it flayed.
* Paladin/Rogue: backstabs galore!
* Paladin/Shaman: windfury + seal of command = critastic.
* Paladin/Warlock: ret pally tanks, dot dot dot with Succubus or Imp pet.
* Paladin/Warrior: fury war and ret pally won't take much damage.
* Priest/Priest: deadly combination; consider one build with Shadow Weaving and another with Blackout.
* Priest/Rogue: keep it stunlocked and flayed.
* Priest/Shaman: difficult, but let your shaman build a little agro before your priest attacks.
* Priest/Warlock: deadly combination; double the fears, double the dots.
* Priest/Warrior: defensive stance will be necessary to hold agro.
* Rogue/Rogue: stunlock it but always have one rogue backstabbing.
* Rogue/Shaman: deadly combination; windfury stunlock for easy kills.
* Rogue/Warlock: voidwalker tanks, dot dot dot, backstab when you can.
* Rogue/Warrior: keep it stunlocked with a fury war ripping it up.
* Shaman/Shaman: unefficient, but use two enhancement builds for quick kills.
* Shaman/Warlock: voidwalker tanks, dot dot dot during windfury dps.
* Shaman/Warrior: windfury'd fury war facemelts so well he barely needs the shaman to attack.
* Warlock/Warlock: Succubus and Imp/Felhound until you both get Felguards, then don't even bother dotting. :)
* Warlock/Warrior: voidwalker tanks in front of fury war, dot dot dot.
* Warrior/Warrior: double your fury war, double your fun.
* Macros are your friend on your carebear. Use the /castsequence reset=X command whenever possible so you're not wasting time trying to remember where you left your flash heal, and put /target Lowbie /follow at the end of every command.
* Follow TOS - don't use software that hack, script or break TOS otherwise GG to you. Chances are if you have to ask is this legal answer is no.
* PvP Servers: be ready for pvp or just die. Get some pvp macros lined up and read ahead on what to do with each class.
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