CD Projekt RED explains how customization works in The game 3: Hearts of Stone
1. Combat
The combat tree was conceived as a starting point for new players. Initial skills are simple and make more effective attacks. Advancing along this path, you can unlock new options, such as turbines (which allows hitting multiple opponents) or tear (a powerful attack against a single opponent).
More experienced players might consider the idea of developing the skills linked to fighting Fury and its resource, the adrenaline. These skills can be very powerful if used at the right time, but require special equipment to make the most of them. About equipment, it must be said as the combat tree is not particularly demanding in this respect. Just get the sword that inflicts more damage and you should be good to go ... maybe.
One of the disadvantages of the combat path is given by the fact that, if you would like to inflict the maximum damage, there will be a lot with which to protect yourself. This problem can be solved with new words and new Rune Glyph marks that we introduced in Hearts of Stone.
For example, you can take the Runic word that Compensation increases health regeneration once accumulated enough adrenaline. Or you can rely on, that glyph will allow you to avoid all the arrows, so you don't have to worry about surprise attacks of the archers.
Overall, the tree is the easiest way to get started, but it may be the most difficult to master. Does not rely too much on the use of objects and, in most cases, you will only need a good sword. Obviously, to fix Death March can complicate things a little, but that's another story ...
2. signs
The tree signs is slightly more complex than fighting and requires more attention about the ability to choose. At the beginning of the game, the choices are limited, both in terms of what you can buy, both for the number of skills you can use. Each sign is effective in one situation and weak in another.
The first sign I want to talk about is Igni. It allows you to attack enemies from relatively safe distance, incendiandoli and removing them from the battle for a certain period.
If you want extra protection, Quen is the right choice. Deciding to invest heavily on tree signs, you can transform Quen in a powerful way. Even without the upgrades, is still a good solution, especially if you have invested a lot in the fight, as it allows you to compensate for the lack of a viable defensive options.
Yrden sign is a must for certain fights, because it allows to cancel some abilities of monsters (take a look at the in-game bestiary for more information). Alone, remains a powerful Yrden sign, but it may take some practice to be used optimally.
Axii sign is an interesting sign, as it can help you avoid a fight by making the right choices in dialogues and influencing the minds of others. At higher difficulty levels, Axii can save you literally life! Who wouldn't like to have enemies that help you win a fight?
Last but not least, there is the Aard. Although sometimes underestimated power of other signs, in the right hands can be devastating Aard. Land an enemy will allow you to delete it with one fell swoop.
The main disadvantage is that signs tree, to launch them, you need to have the maximum resistance. Since they serve some precious seconds to recharge the battery, it is crucial to launch the OK sign at the right time. There are words and signs of Runic glyphs that can help you maintain strength. The Runic Word Invigoration instantly restores lost strength part, while a sign of Protection glyph will activate Quen without consuming the resistance when you enter combat.
There are words and signs of Runic glyphs that allow you to reinforce the shaft signs, but I leave you to discover the pleasure of playing Hearts of Stone.
3. Alchemy
Alchemy tree is the most complex of the three and requires some effort and some dedication to exploit it to the fullest, but worth it. If you want to become a virtually invincible, take recovery, protective coating and Transmutation. With heavy armor and some mutagenic green vampire, you might turn you into a veritable force of nature.
It is highly likely that you will be able to maintain maximum health by choosing the word Invigoration, Runic also allows to increase the damage. With this active, Rune word any type of care used when your vitality is at maximum will increase the damage of the next attack with your sword.
You might opt for bombs and efficiency to wreak havoc by exploiting the many bombs at your disposal. Test skills of herbs might be a good choice for lovers of risk. They require that the player is poisoned by potions, but give some of the most powerful skills of the game.
The main disadvantage is that Alchemy tree requires a lot of creation. You'll have to arrange numerous alchemical recipes and reach level 3 as soon as possible. To do this, you need a lot of time and money and for this reason, the location Alchemy starts to get interesting only in advanced stages of the game. The downside is that it doesn't require any particular weapon or armour to be effective. Take what you like and enjoy blowing things!
These recommendations should be enough to take the path that will take you to become a ammazzamostri machine. Remember that the game is full of choices and decisions to make, so don't be afraid to experiment!