The cool thing about Path of Exile is that as long as you fulfill stat requirements, you can use just about any active skill as long as you put the gem into a corresponding slot in one of your items. That gem then levels up as you use it more and makes the active skill grow stronger. Despite the accessibility to these skill for just about every character class, there is still bound to be those that get used more often than others due to their utility and effectiveness.
Here are five of the best skill gems that get used more in Path of Exile items. They're used for their utility and effectiveness against enemies, as well as being fit for certain character builds that end up being really good.
This is an attack skill that consists of an initial single-target fire melee attack, then followed by an AoE fire projectile attack. The area of effect of the projectiles spread throughout a 270-degree arc within a radius of 5 to 20 units, which can then be enhanced for better effect and more damage. The various properties of the magma projectiles, as well as the melee fire attack itself, give this skill plenty of damage that can then be enhanced with other support gems.
It's basically a trap skill that explodes when triggered, leaving fire in its wake that damages all enemies that happen to walk upon it. You'd think that traps don't get as much use in this game, but Fire Trap has quite a bit of utility even in the late game as it's useful for doing extra damage while kiting enemies.
This is a familiar skill to anyone who has been playing action role-playing games for a long time now. The Leap Slam basically lets your character, most likely a Marauder, jump high up in the air at a distance and land with devastating force, damaging enemies in the surrounding areas with a chance of knocking them back. This is a melee attack that must be used with melee weapons and the required amount of Strength.
This is a projectile skill using your current melee weapon, like how the Norse god of thunder Thor would throw his hammer Mjolnir with devastating effect and have it boomerang back to his hand. If the character moves after throwing the weapon, it will home in back to his hand. This skill has a 100% chance of piercing through enemies, so Piece, Chain, and Fork are not necessary. You can augment it with Multiple Projectiles though, as well as damage modifiers, range, and projectile speed for greater effect.
You'd think that gimmicky skills like this don't get used in a no-nonsense game such as Path of Exile, but it actually gets quite a bit of use. The Decoy Totem is great for acting as a meat shield that draws enemies away from you, which then enables you to hit them with some other skill that takes them out in that area. You can augment Decoy Totem with Increased Totem Life for more durability.