But it requires much investment to be really effective for speed farming. I will try to break down what I think about Amazon's bow skills:
1. Trinity Arrow: If the enemies come into its contact exactly at the impact center, then the damage is really tremendous. However that is based on a per-shot basis. And while you may hit the enemy quite easily, even with the somewhat slow projectile, it is hard to land the impact center on the boss. Unless the boss does not move much, or not at all (e.g. Astrogha, Death Projector,...). For moving boss, summon/reanimate can keep its busy and staying in one position, or you can even face-tank the boss, however doing that with a glass-cannon bowzon is not really a good idea. This skill also costs hefty amounts of mana. Due to its handling and situational nature, 1 point is enough for me, I prefer to spend the points on more reliable skills, and effective passives.
2. Barrage: I like the idea if skill, it is very cool. But it really needs more are coverage, especially toward the further areas it reaches. It works well when you are right next to the enemy. And running up into a mob's faces is suicidal for a 0-defense bowzon. Barrage converts 99.99% physical damage to tri-elemental, making it into an even more suicidal skill. Enemies around the outer part of the skill's are dealt too little damage IMO, since they cannot be multi-hit, instead only being hit by 1 arrow each barrage. That being, making more arrows to cover the outer areas may also mean too many arrow around the inner areas, making it imbalance. Quite a tricky skill to treat indeed. Luckily just 1 point into the skill and you can cast it without timer.
3. Phalanx: Amazing, versatile skill, boss killer and mob killer. Though it requires some practice to cast effectively, it brings you the benefit of not having to face the boss/enemies directly, thus greatly increase survivability. But Ironically, the large number of amazon images it create can cause many deaths in Tran Athulua, since you won't easily be able to spot out Amazon Defenders and their cheap Arrowsider procs. This skill requires 10 points into its passive upgrade to remove timer, but the investment is worth it.
4. Wyrmshot: The area coverage is just absurd, but only attainable after many points puts in the skill itself and its passive upgrade. This skill is the widest-area farmer I have every tried so far.