My experience as both 23 Assassin and 23 Ranger.
I've always known from the start I was going to be a scout. Determining which path I would take required me to level both to a level high enough for the class to become its own. I chose 23 mainly because I had 2 chainskills and level'n after 23 sucks.
Ranger:
I took ranger up first. After ascending and swapping my main weapon over to a bow I noticed the kill speed was horrible from 10-20. There's a very easy fix for this. Make use of you weapon swap.
The best way I found to kill fast would be to initially pull with my bow using the skills I have and once then mob got too close I would use Focused Evasion followed by a weapon swap -> Counterattack -> Surprise Attack and either the chain swift slash or swap back to my bow and swift shot. This usually kills the enemy up until about 14-15. If not it's nearly dead.
At 16 you get a new shot that ups your damage with bows by a lot, however there's still a downtime after using all your abilities with your bow. So once again it's best to swap to your melee weapons and use the above tactic.
Once you get the Swift Shot chainskill using a bow becomes your main priority. Occasionally there will be downtime between your cooldowns allowing you to swap to your daggers or sword pop focused evasion -> counter attack -> surprise attack. If you do this it's best to swap back to your bow and finish it off with your bow's chainskill.
Leveling in parties was pretty fun as I had snare shot incase we had aggro I could kite one around while damaging it to keep hate. Spike trap helped also.
I had the chance to kill a few Asmodians as ranger and I can say it was pretty fun. The +200 evasion skill rangers get makes a huge difference in PvP. Having the ability to damage from afar is also a major plus.
Assassin:
Assassin was second on the list. After ascending I decided to use Dagger in my mainhand with a Sword in the offhand. At lower levels it's considered best to use a Dagger for your mainhand due to the 5% additional crit you get.
Leveling as an Assassin was pretty simple. It's the same as scout pretty much up until 16. At 13 you get your first pattern skill, Rune Carve. Which can be useful but by the time your patterns get to level 3 the mob is already dead. 16 is the turning point for pattern skills. You get your second pattern skill, Fang Strike at 16, which makes your kill time even faster. For me I would open up with a Hide Surprise Attack -> Focused Evasion -> Chainskill Swift Edge -> Counter Attack -> Rune Carve -> Fang Strike. Repeat once and explode your patterns.
20 Was really nice level as you get your 2nd chainskill which is another pattern skill Sigil Strike further increasing the ability to add pattern strikes to your enemy.
For those who don't know what pattern strikes do I'll explain. Using a pattern skill such as Rune Carve or Fang Strike has a chance to put a debuff on the monster (roughly 50% in my opinion) The debuff can stack to 5. The higher stack you have when you use Pain Rune the more damage the pattern will explode for and the higher chance to stun the enemy.
1Stack = About 40dmg
2Stack = about 100dmg
3stack = 360 dmg
4stack = 400+ dmg
5stack = 400+ dmg
I don't have much PvP experience on my Assassin but I know that dueling clerics 1v1 is pretty tough.
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