The Witcher 3: Wild Hunt Guide to Character Progression

Introduction
Like many RPG games The Witcher 3: Wild Hunt has extensive character development and levels. Unlike many games, however, gaining levels doesn't give very many character stat benefits by itself. Witcher 3's character development is almost entirely based on an unlock-by-level system; the higher your level, the higher the level (and therefore stats) of the equipment that you can wear and the more skill slots you unlock, on top of the additional skillpoint per level. So to understand this you also need to understand the Equipment, Skills and Mutagens that fuel it.

Equipment
Geralt 's strength growth from equipment is fairly straightforward: the higher his level the higher the level of the equipment he can wear, and higher level equipment has better statistics. There are also several different grades of equipment for each level.

Weapons
Your main tools for inflicting death on your opponents, and you'll be using them extensively.
 * Steel Swords: Your primary weapon against non-magical enemies such as people and animals.
 * Secondary Weapons: A mixture of weapon types including axes, staves and clubs, but despite the name you can't actually dual wield one of these with your steel sword; equipping one replaces your steel sword, and they often work differently.
 * Silver Swords: Your primary weapon against magical/undead enemies. Going by the numbers these have significantly higher DPS values than equal level Steel swords, but the undead enemies they are intended for also have higher health to compensate for this so don't expect to mow through them quickly.
 * Crossbow And Bolts: You obtain your first crossbow during your hunt for the Griffin, and interestingly enough you can still fire it with no Bolts equipped; you have an unlimited number of basic Bolts available which means your shots will do damage based off of the Crossbow alone. You can craft/find/buy better Bolts and equip them but Witcher 3 does have ammo consumption for the special bolts, so once you run out you'll have to get more or rely on the basic bolts alone. This will be your primary ranged weapon.
 * Bombs: You have inventory quickslots to equip two of them. Forged through Alchemy and thrown like a grenade, there are various types of bomb that can damage or stun groups of enemies. Given the moderate rarity of their ingredients you won't have these in large numbers and therefore won't use them heavily in combat, but there is one other key note on them: the Grape grenade is one of the only things that can destroy a Monster Nest, so make sure to have plenty of that one on hand.

Armor
You have 4 armor piece slots: chest armor, pants, gloves and boots. That by itself isn't particularly important; what really matters is which of the three armor Types each piece is and how this ties into your Skills, since there are certain skills that when fully trained give you strong bonuses per piece of a specific armor type that you are wearing. Since you don't get enough skillpoints throughout the game to max out every skill nor enough slots to wear all of the skills you should pick one armor type based on your intended playstyle and stick with it to make it very strong; it will literally define how you approach every fight you get into.
 * Light armor gives the lowest defensive boost, but when paired with the proper skills gives the highest general combat damage boosts by heavily improving your quick attacks and critical rates/damage. You will need to get quite comfortable with the dodge and roll moves to make up for the lack of raw protection, which makes this build and corresponding fast-attack-and-dodge fighting style surprisingly similar to combat games like Devil May Cry.
 * Medium armor gives moderate defense and strong boosts to your Stamina regeneration, making it an ideal choice for people who want a more mage-like build firing off Signs as often as possible.
 * Heavy armor gives the highest defense and also boosts your Strong attacks, leading to a slow-but-steady tank-like style of fighting.

Accessories/Consumables
On top of your armor and weapons you have an extensive array of supplementary equipment and items available to you, some of which actually get equipped on your horse Roach.
 * Consumables: You have 4 quickslots available to you with hotkeys set on them for quick use, and you can equip any food or potions in them. This will be your primary source of healing for a fair chunk of the game.
 * Saddle: Equipped on Roach and starting off with an initial basic one, this mainly determines the maximum Stamina Roach has when you have him go at a full gallop before he gets tired.
 * Saddlebags: Also equipped on Roach, this mainly determines the maximum weight of items you can have in your inventory. Some items like herbs and quest items are considered weightless so you can have mountains of them in your inventory, but equipment doesn't so you'll want a good set of Saddlebags to prevent yourself from having to go back to a merchant to sell your loot too frequently.
 * Trophy: Usually a body part of some legendary monster (eww), these give a variety of permanent passive effects such as increasing your chance of beheading enemies on a hit, boosting your experience gain, etc...you get your first one after defeating the Griffin.

Skills
To be continued...