At level 20, you will begin to move into harder parts of the land, but you will also gain better skills and abilities as well. Some of these areas include: the Forsaken Inn, Ost Galumar, and Bindbole Wood, and are where the majority of the Hunter specific quests are found. While the mobs in this area become higher level and harder to kill, your skills and abilities will also help you to deal with these newer mobs and help you to keep your group, or yourself, from taking too much damage. Once you hit level 20 and begin to move into other areas of the game, make sure that you take the time to hit the hunter trainer as often as you can so that you are always on top of the skills and abilities that come with each new level. While most of the main skills are learned at even levels, LOTR is not like other MMO games which only has you training your class at even levels. You can gain new skills and abilities all the time, so be sure that you check with your hunter trainer constantly as you up your levels.
Once you hit level 20, you will find that your hunter will really come into it's own. With new skills, abilities, traps, and more, you will become a force to be reckoned with. At level 20, you can start to use Fire Oil on your arrows that will allow them to deal additional fire damage over time after they strike an enemy. You will need to train in the Use of Fire to be able to use Fire Oil, so make sure that you do this when you hit level 20 and purchase the Fire Oil from the hunter trainer while you are there. If you choose to become a Scholar, then you will be able to craft this oil, and several others, to save you time and money.
Along with this new addition to your arrows, you will also learn several new traps that can help you hold the enemy and do more damage. You will learn Multi-Trap, which allows you to lay two traps at the same time that will trap up to two different enemies. This is great for group play or for areas when you get ambushed while soloing. You also learn Improved Bear Trap, which will inflict much more damage on your enemy.
To help in your hand to hand combat skills, at level 20, you can learn to Dual Wield so you can attack a target at close range with two weapons instead of one. This does more damage and increases your melee output by over double. To add to your tracking skills after you hit level 20, you will gain many great tracking skills. One is Passage of Foes, which will help you track humanoid creatures, both enemies and friendly targets.