Bungie detailed many of the changes and gameplay improvements coming to its addicting interplanetary MMOFPSRPG Destiny in a Twitch stream this afternoon. It was the first of three scheduled livestreams exploring the world of The Taken King, which is set to expand and completely overhaul Destiny when it's released on September 15th. (It's different from The Dark Below and House of Wolves, the two small DLC packs released in the year since vanilla Destiny's launch last September.)

The stream featured executive producer Mark Noseworthy, senior design lead Tyson Green, and community managers DeeJ and Cozmo, and it focused on the mechanics of character development and the refinement of core gameplay elements rather than new environments or the game's narrative. Bungie has had its ardent fanbase hooked on a slow drip of details since the expansion's reveal at E3. The Taken King was further fleshed out by a mammoth Game Informer cover story and related online updates, but the Twitch stream officially confirmed some features and paths that fans have been speculating about for weeks. Here's a quick review of those changes:

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1. Levelling is easier to understand

If you've played a lot of Destiny before The Taken King, you can probably recall the moment where you first puzzled over the game's bizarre levelling system. Vanilla Destiny players advanced through earning experience until Level 20, at which point any changes in their level became tied to their gear. Pieces of armor had Light values that were added together to yield some total, meaning that your level — and thus your effectiveness against the game's toughest enemies — was tied up in the armor you were wearing.

This was a source of immense confusion for players, and the system has been simplified for The Taken King. Players can now reach the new level cap of 40 through earning experience — completing story missions, going on patrols, running strikes, playing against others in PvP, and other standard activities. Light still exists, but it's an indicator of overall strength rather than something that impacts players' access to content. (It now factors in the strength of your weapons, class items, and Ghost shells rather than just your armor.) Bungie described its impact on player strength as "more granular."

If you attained a certain level using Light in vanilla Destiny, it'll be ported over to the same XP-related level once you hop into The Taken King. Your new Light level will be automatically determined by the contents of your inventory and vault, and Bungie has recommended waiting to dismantle anything until that level has been calculated.

2. Weapon stats, slots, and special skills have been recalibrated

I hope you're not too attached to weapon damage and defense figures reaching the mid-hundreds, because those numbers are going to change. The armor and weapon damage values that characterized vanilla Destiny have been knocked down by over half, and they've been aligned so that weapons and armor with the same attack / defense values are roughly equivalent in terms of strength. (One of Bungie's streamers said it's like "switching to the metric system.") A lot of gear will still be available at level 20, but much of The Taken King's new armor and weaponry will be locked until players reach the new level cap. Strength, intelligence, and discipline have been newly tiered and separated from percentages, and looking at them will tell players their exact impact on cooldowns.

Class items and Ghost shells now contribute to attack and defense as well, and they've been granted specific perks that impact gameplay in new ways. An example is the Winter Sky Shell, with flavor text "For Ghosts who feel blue"; it aids XP and / or reputation gain, and other shells do too. Other armor pieces have also been given newer, more specific perks. There are also new ways to extract value from unwanted armor and weaponry. Legendary armor will yield Legendary Marks when dismantled, and legendary and exotic weapons and armor can be upgraded through Infusion, which lets you "consume a more powerful weapon to boost the attack value of [a] weapon."

3. Get ready to flip through Exotic blueprints

Exotic weaponry is changing in a major way in The Taken King. The Tower is full of terminals that contain a catalog of every exotic you've found, information that spans your whole account. New exotic weapons can be built using exotic shards and a small amount of Glimmer. Some exotic weapons from vanilla Destiny can be upgraded to the new maximum attack value right away, but others will be left behind at their old attack values. Finally, exotic items now have their definitive perks unlocked right away — you won't have to grind and grind just to discover what makes a given weapon special or powerful.

4. Currencies and reputations have been simplified

Bungie's heard the sob stories about PvE-dominant players staring longingly at Lord Shaxx's sexy Crucible-specific gear, and it's here to help. Vanguard and Crucible Marks — the high-value items used to buy legendary weapons and armor in the Tower — have been combined into a single item, Legendary Marks, and they can be used at any of the Tower's retailers. Upgrade materials have also been scaled back, with all three class-specific materials now folded into a single collectible. (Goodbye, Sapphire Wire! So long, Plasteel Plating! Good riddance, Hadronic Essence!) Players' wallet of marks is still capped at 200, but the weekly earning cap has been lifted — you can earn as many as possible in a given week.

Players can also pledge their allegiance to one of the game's factions — there's New Monarchy, Dead Orbit, and the Future War Cult — by paying with Glimmer where they once had to wear a faction-specific item. (You can only change allegiance once a week, and you can only hold one at a time.) You can now earn faction reputation and Vanguard / Crucible reputation at the same time, a major change from vanilla Destiny's exclusivity, and reward packages earned by increasing rank have been improved too. There are also faction-specific quests unlocked by achieving certain ranks.

The Taken King's also introducing some new reputation receptacles, most notably the Gunsmith. Once a meaningless purveyor of sub-standard weapons once you surpassed Level 20, he's been revamped and turned into a regular source of legendary weapons. You can field test weapons, which means "renting" them from the Gunsmith and completing a task; doing so gives you a small amount of reputation. Once you've earned enough favor, you can participate in Armsday, a weekly legendary weapon delivery from one of the three new weapon foundries (Suros, Häkke, and Omolon).

5. I hope you like quests

Vanilla Destiny had many problems — and if you're even the slightest bit familiar with the game, I'm sure you've heard all about them — but none more glaring or befuddling than its terrible story. The game tossed you into a vast universe and gave you insane powers and weaponry, but didn't bother to explain how you obtained them or why you were important; its most infamous scene involved a character — named "The Stranger!" Seriously! — telling your nameless hero "I don't have time to explain why I don't have time to explain" before vanishing into thin air. I'm honestly still not sure why the game's called Destiny in the first place. You just had to get used to Peter Dinklage's robot monotone and accept that you'd spend hours killing bad guys while he opened doors for you, without a scrap of justification or explanation.

Bungie knows this is a problem, and it's reframing the entire game's narrative around quest lines with The Taken King. This is a change that's going to apply to existing content, too: if you've ever wondered about the lore behind becoming a Bladedancer or the significance of the Crucible, it's going to be explained through a quest now. Much of the new content in The Taken King will only be accessible through the completion of multi-stage, lore-rich quest lines, and it'll be paired with new cutscenes and increasingly rich characters. Destiny's finally putting that army of quality voice talent to good use!

6. Bounties are different too

Bounties have been revamped to reflect actual play patterns — you won't have to beat the same boss over and over again just to earn a small bit of experience. Players can track up to four bounties, and doing so will show progress on those bounties when they pull up their Ghost during gameplay or in the Tower. You can also cash in your bounties from the pause screen, a change that's surely going to eliminate millions of extra trips to the Tower every day.

More vendors have bounties that are specifically tailored to their function, and there's a new level of differentiation between daily and weekly bounties. Bungie's team of streamers looked at a selection of weekly bounties that had to do with PvP play, and revealed a special bounty that's completed by finishing a certain number of weekly bounties. If you manage to fulfill that special bounty, you'll have access to unknown "Nightfall-tier" rewards.

7. You can give your character a little boost

Players who purchase The Taken King will be given a "Spark of Light," a new item that lifts characters to level 25 and outfits them with "appropriate gear." It also unlocks The Taken King's campaign. The item can't be used on characters above level 25, but it'll allow new players to jump right into the new game's action rather than forcing them to work through all of vanilla Destiny. (They'll still be able to do that if they want, though.)

8. Appearance stuff and Tower reorganization

Bungie is making a whole host of minor changes to the Tower's organization and to player appearance. You can now choose the weapon you want your character to carry in the Tower, and you can look at your face without a helmet on the equipment-centric pause screen. Emblems, shaders, and ships are now contained within terminals throughout the Tower, and they track your acquisitions over time. If you delete one of those items, you can acquire it again through those terminals. Factions now allow players to exchange materials for reputation, a quick and easy way to turn some excess armor materials into a higher rank.

Some vendors have moved, and others are selling new items — for example, the Speaker now sells Ghost shells in addition to his existing class items and material exchanges. Finally, some vendors have been tweaked to offer more deterministic and endgame-appropriate rewards. The most notable example is the notorious Cryptarch, a mysterious magician who's ripped off millions of players over the course of his year in the Tower. He now sells legendary engrams for Legendary Marks, allowing players a guaranteed legendary item and a chance at an exotic item.

9. Vault space — yes, really

Devoted Destiny players have been screaming about vault space for months. Many of them have earned so many exclusive or rare pieces of weaponry and armor that they have to cycle them between characters — there just isn't enough storage space to accommodate them all. Bungie is trying to remedy this by doubling the vault space for both weapons and armor, a move that should satisfy all but the game's most devoted players.

Playing The Taken King won't bring back Dinklebot or earn you a shiny new Gjallarhorn, but it should make for a radically different — and more satisfying — Destiny experience.