Neither me nor my collaborator own Sword Art Online or dotHACK/GU. This fanfic isn't just a crossover, it's an attempt to rewrite both universes entirely. Within this universe, The World R1, The World R2, the game Sword Art Online, and Alfhiem Online DO NOT exist. Instead our best attempt at an amalgamation of R2 and SAO called World of Blades. Due to crossover interaction some characters have new affiliations or are different players entirely. For some characters, they may seem OOC (out of character), this was our attempt to fix one of the biggest problems with both series; an overall lack of good characterization. Now I will describe World of Blades' systems, or a basic rundown of it.
Skills and Levelling - A lot like Skyrim but with more skills and perks. For those of you unfamiliar with Skyrim, everytime you increase your skill level in something (in the case of World of Blades anywhere from 1 to 1000) you gain experience towards your next character level. Every character level allows you to grant an extra boost towards health, mana, or stamina as well as a perk point to a perk or arte available with one of your skills. Unlike Skyrim, though, you still gain experience points from killing enemies.
Magic and Artes - Only when you use a certain weapon are certain artes or spells available to you. Most spells, especially healing spells are both equip spells and ready-to-use spells. Any equip spells or artes you use, by that I mean the spells and artes you have access to while a weapon is equipped, consume stamina with each use. Ready-to-use spells can be used without having an appropriate weapon equipped. Stamina acts similarly to in Dark Souls, the difference being that it's not consumed with every hit, only when you activate an equip spell or arte. Blocking and "charge attacks" also depletes stamina. Mana is pooled when you're in a party and is consumed by ready-to-use spells, stamina is not. Stamina recharges during battle and while wandering around, mana only recharges while wandering.
Drops - Not just items and currency can be dropped by enemy monsters. Skills, perks, artes, and spells may also be dropped. A rare item called a "Tuning Fork" is needed for any equip spells to drop. All drops share Destiny's rarity classification; Normal, Uncommon, Rare, Legendary, and Exotic, with an additional classification called Divine. Divine drops are items only, no matter how much you use them they do not deplete, they can be stored but not traded, transferred, taken, salvaged, or sold. Skills and perks are dropped in the form of scrolls and artes and spells in the form of tomes, none are to be confused with grimoire weapons, skill books, or item blueprints.
Items - Weapons, armor, clothing, tools, consumables, alchemy, cooking, materials, enchanting, and barter. All items Rare and below have a durability that either depletes with use or over a set period of time.
Weapons - Twin Daggers, Longswords, Greatswords, Scythes, Lances (though they resemble huge drills), Great Axes, Kunckle-Gauntlets, Rifles, Twin Handguns, Gatling Guns, Railguns, Caster Rifles (they fire spell-infused bullets), Staves, Grimoires, Throwing Knives and Twin Fans. Most gun weapons still require ammunition to fire, the exception to this rule are Gatling Guns and Railguns, which consume stamina and in some cases mana to fire.
Armor - Heavy, Light, and Robe class of which there are Helmets, Armors, Gauntlets/Gloves, Boots, and Accessories. Generally, they're only meant to augment your damage resistence but can have other effects if enchanted.
Clothing - Self-explanatory. Typically worn around towns instead of armor.
Tools - Useful for Blacksmithing, Gunsmithing, Spellcrafting, Cooking, Alchemy, and Enchanting. Each of these skills have specific tools associated with them and are labelled appropriately.
Consumables - Health, stamina, and mana potions as well as other such items. Some can be used multiple times or have several different uses.
Alchemy - Ingredient items used to make potions and poisons, some may also be counted as cooking items.
Cooking - Ingredient items used to make in-game foods, some may also be counted as alchemy items.
Materials - Ingredient items used in Blacksmithing, Gunsmithing, and Spellcrafting.
Enchanting - Soul gems, along with several varieties of enhancement stones.
Barter - Barter items have only 2 uses, as a stashible form of currency or to sell.
Skill Trees - One-handed, Two-Handed, Defending (blocking, countering, and parrying), Marksmanship, Stealth, Lockpicking, Pickpocketing, Speechcraft, Restoration, Destruction, Support, Blacksmithing, Gunsmithing, Spellcrafting (the forging of staves, grimoires, and twin fans), Cooking, Alchemy, and Enchanting.
Player homes and shops - Players can own their own houses, shops, inns, taverns, and even entire areas if they buy them or lease them. When an area has been bought or leased the owner can charge a toll to enter the area or can restrict other players from entering at all. They can also build player dwellings in these areas.
Areas - Along with fields, dungeons, guild areas, and Lost Grounds there are also race-tracks to race hover-bikes, hunting grounds where multiple players chase a single monster, and sports fields which are self-explanatory.
If you have any further questions, leave me a comment and I will address it.