In another article, we covered the passive skill tree explaining its mechanics and how it affects the gameplay and progression of your character. But how exactly do you acquire active skills if the skill tree is only for passives? Well, in this article we will talk about active skills and the way you can acquire them via the game's skill gems.

Most of your active skills come from items called skill gems, which need to be socketed into your equipment to be used. Most equipment items come with colored sockets. Gems must be put into sockets of a corresponding color, simple right?

The depth of this system comes from the fact that there are two main types of gems: active skill gems and support gems. The first category is pretty straightforward, once equipped they will give you an active skill. Support gems work a bit differently. They are used to augment active skill gems and cannot be used on their own. Think of them as attachments on guns: on their own not very useful, but once installed they can help you tremendously. 

Another crucial thing for support gems to know is that they only provide their effect for  an active ability if the two gem slots you put them into are linked (connected) to each other. Support gems of the same type cannot be stacked, only the highest level will take effect in that scenario. You can either look for equipment that has your preferred variation of sockets or take things into your hand and reroll links with the currency item orb of fusing. This method works on slot colors as well. In their case, you can use a chromatic orb to do the recoloring.

Okay, so now you know a bit about gems, but how can you get them? The answer is quite simple, they can come as quest rewards, you can buy them from vendors, they can drop from monsters or chests or you can acquire them from vendor recipes.

An interesting aspect of gems is that they level up just like you. Socketed gems gain 10% of the experience your character earns, calculated before any level penalties. After a gem's XP bar gets filled, you can click on it to level it up. As gems increase in level so do their stat requirements, level and mana costs. It has to be noted that if the level up icon is grayed out then you do not meet the requirements.

Most gems have a level cap of 20, but there are several ways to go beyond. Namely: Paragon's +1 to all socketed gems prefix, corruptions, or certain unique items like the Frostferno. Even some support gems can augment gem levels too. By these methods, you can increase a gem's level substantially.

Gems also have qualities, which determine the effects of the given skill. Quality can be upgraded by the gemcutter's prism currency item. The exact modifications quality gives to a gem can be seen in the detailed view.
The effect of quality will scale with the base quality's effect, but only whole numbers will be granted. for example, 3% quality on a gem with 0.5% effect will only grant 1% effect and not 1.5% effect. Effects that have some degree of fractions are rounded to their natural bases. In the case of seconds, it will be rounded to milliseconds.

As we mentioned gems can be corrupted by Vaal orbs possibly raising their level. However, it may also convert the gem into its Vaal skill equivalent if one exists.

There are two special types of gems we have not talked about already. These are awakened gems and alternate quality gems.

Awakened gems are just support gems on steroids. Basically, they are much more powerful versions of their regular counterparts. They are so strong that a level 1 awakened gem is equal to a level 20 regular gem. Since they are this powerful they can only be leveled up to +5. They are late-game drops from bosses like Sirius, Drox, the Maven or Al-Hezmin. 

Alternate quality gems come from grand heists. Besides the base quality, there are three alternative qualities (anomalus, divergent and phantasmal). With these in mind, there are several variations far in the hundreds.

We hope this guide helped to understand how gems work and affect the gameplay. Stay tuned for more guides on PoE!