Here are some advices on Shaman builds. You may choose to build yours differently based on how you would like to customize your character, which is as it should be. If you choose to build your character those primary attack skills you will encounter.
   First thing first, Fireball level 5 is single-target spell which is the first skill you can take and it's the best one you've got. With only a 0.6 seconds cool-down time, FB spam-mage is clearly at hand. Use it, don't regret it, use it and use it often. In between cool-downs you'll have the chance to take a swing at the mob, so do it but only one swing, and then back to another fireball, swing, fireball, swing. Better yet, alternate FB, Fire Arrow, FB, Soul Expl, FB for 1000 pts of instant cast spam-mage damage when you absolutely, desperately need something dead in about 2.5 seconds and when you care nothing for MP efficiency. FB starts strong and remains your primary attack throughout the game largely due to instant cast and super-fast cool-down time.
Secondly, Fire Totem level 5 is an outstanding skill offering serious damage output. And you get it fairly early on. At level 5 it does 330 DMG per target, up to 8 targets, with an additional base continuous DMG of 13/2 per target of burning damage for 10 seconds. The first DOT of fire totem, the 330 DMG, is not modified by INT. The second part, the continuous burning DMG, increases as your INT increases, as is true with fireball, most spells in general, and all elemental DOTS that I have seen. Since DNA cannot be used to increase DOT aspects of Shaman skills, this is another reason why INT is so important for increasing your damage per second.
   Burning Hell has its drawbacks, so let's get those out of the way now. It has a 1.5 seconds cast time, which is the fastest cast time of a spell not instant cast, but a fairly long cast animation, however it is cancelled by any type of movement at all. Even after the 1.5 seconds cast time has elapsed, if you move your character at all during the ensuing cast animation, the spell will fail to fire off. If you attempt to cue up the next spell you wish to cast, at any point before burning hell actually fires off, the spell will fail to cast and you will instead cast the other spell. Also, you have to be facing your target, within about 60 degrees either to the left or right of your intended target, otherwise the spell will fail to cast.
To max Healing Totem out needs continuous supportive party heals out to great distance. Mine was level 4 at end of CB, with level 5 becoming available at level 42. No DNA is available for non-setting-stuff-on-fire skills for shaman. Ha. Duration of spell goes up with each successive skill level purchased, with only marginal increases in per tick healing. Major downside is the 2.5 sec cast time, which means that you better throw them before combat starts b/c in 2.5 seconds you can do a lot more DMG than one more healing totem is going to be worth in terms of healing in during that time. Still, they stack, you can have up to three out at a time, and at level 5 each one lasts for 30 seconds, healing for 15/2 any party members within 9 or 10 meters from it for that whole time. Cast one or more before a battle, if needed, to heal up from damage you will take in the next 15 or 20 seconds or so. Get it, max it, even though it doesn't kill stuff. Healing totem is no replacement for a skilled Templar or Radiant healer.
Soul explosion needs instant cast and long cool-down time. At one time, it is up to eight targets and no continuous DMG. Typically most mobs close to melee range make Soul Explosion useful in spamming with other instant cast spells for fast DMG.
   Get and max Flame Shield. One of the few percent - based DMG mitigation buffs in the game. If the mob scores a critical hit, and you get a successful reflect DMG roll on this skill, and then the DMG reflected back at the mob is correspondingly increased too. DNA is available to increase the amount of DMG reflected back at the mob, but not to allow you to increase its success rate. Past level 3 this skill really opens up and changes your game-play if you let it. Get this skill at the very first opportunity it becomes available, and max it out quickly, the DNA as well.
   The above is based on the choices we made based on our own judgments and you should make whatever choices you are happiest with in customizing and building your unique Shaman character. If you decide to roll a Shaman, we hope this content is of help to you.