(Most of this information can be found on
Paragon Wiki or from the Inventions lab forum on the
CoH Invention board )
I wanted to consolidate some general information in this post. Note: For the rest of the document I will use Wentworths as an example. Any time you see Wentworths, and you play red side, just pretend I said Black Market Truck. I use inf to indicate influence and infamy.
The Basics
What the heck are IOs? IOs are Invention Origin enhancements. When you first hit level 10, or first go to Steel Canyon (or Cap au Diable if you are villainous) if your character is already past level 10, you will get a new contact: the university admission officer. They will give you a series of contacts that have little mini-quests to learn the IO system. You DO NOT have to do this to use or make IOs, but I recommend doing it at least once so that you have basic information about the system.
What do they do? The generic IOs function just like TOs/DOs/SOs they enhance one aspect of a power.
OK, so why go to the trouble to build/buy these things? They never expire. Yep thats right, if you slot a level 15 accuracy IO at level 12, its good till level 50. But, it stays at the same value its entire life. Example you slot a level 15 accuracy IO in brawl. At level 12-50 that IO always gives you a +19.2% to accuracy. Compare that to a DO that gives +16.67% accuracy and expires.
OK, so IOs sound interesting, whats the catch? You have to invent them (or buy them on the consignment house). Inventing IOs requires a recipe, salvage, access to an invention table, and influence (or infamy for you nefarious rapscallions).
How To
OK, where do I get a recipe? Recipes can be found as a drop from mobs of level 10 or higher, or reward for completing a mission, trial or task force. For common IOs, the only sources are mob drops and the invention table. Yep you can buy the common IO recipes from the table.
OK where do I know what salvage I need? To find out what salvage you need to craft your IO (or costume piece or temp power), you need to open your recipe list. For recipes that were mob drops, you have personal recipe storage, you can view whats in it by looking on the same window where you manage you inspirations and enhancement drops. There are two new listings there from Issue9: salvage and recipe. If you are buying the recipe from an invention table, you scroll through the list until you find the recipe type, click on that and you see level ranges. Click on the level IO you wish to craft and it opens a description of the Io, including what salvage you need. It also has a buy button, and if you have all the necessary salvage, a create button.
Hey! My salvage (or recipe) link turned red, what gives? You can only carry so much salvage and recipes on your character. The good news is that limit increases as you level. (for exact number, the paragonwiki has them, scroll down to the
Inventory Storage ) The other good news is you have personal storage, available at the Vault (most zones, including Pocket D, have a Vault, you can find it on the in game map). If you belong to a super group, your base editor can also add a vault access to the base. You click on the vault door and it opens you personal storage (note this per character not per account, so if you play Captain Courageous and Major Disaster, they cant access each others personal storage), then you can drag salvage from your salvage window into the personal storage window. You personal storage is the same as your characters storage and grows at the same rate. The off character storage is just for salvage there is no off character storage for recipes.
OK where do I get salvage? Invention salvage occurs as drops from mobs of level 4 or higher or buy at the consignment house. Certain mobs drop certain types of salvage.
[u]Magic:[u] Banished Pantheon, Cabal, Cap au Diable Demons, Carnival of Shadows, Circle of Thorns, Fir Bolg, Ghosts, Hellions, Lanaruu, Minions of Igneous, Psychic Clockwork, Red Caps, Rularuu, Slag Golems, Snakes, Spectral Pirates, Tsoo, Tuatha de Dannan, Wailers, Warriors.
[u]Tech:[u] Arachnoids, Cage Consortium Guards, Coralax, Council, Crey, Devouring Earth, Dockworkers, Family, Freakshow, Gold Brickers, Hydra, Infected, Knives of Artemis, Legacy Chain, Lost, Luddites, Malta, Mooks, Nemesis, Outcasts, Paragon Police Department, Rikti, Rogue Island Police, Security Guards, Shivans, Skulls, Sky Raiders, Spetsnaz Commandos, Trolls, Turrets, Vahzilok, Wyvern.
[u]Both:[u] Arachnos, Clockwork, Longbow, Scrapyarders, Void Hunters.
ANY mob level 4 or higher can drop salvage as long as it cons as a color (grey mobs do not drop invention salvage, green and upwards do). Click on the mob, select information and the window that pops up now has two tabs: information and salvage. Information is the default and it gives the same data it has given for the last 8 issues. Clicking on the salvage tab tells you all the salvage that could potentially drop from that particular mob. Note that a mob can now drop up to five things at once: an inspiration, an enhancment, base salvage, a recipe, and invention salvage. The chance of a drop from a mob looks like this:
Minion: 8%
Lieutenant/Sniper: 10.64%
Boss/Elite Boss: 25%
Archvillain (Rewarding): 43.22%
Salvage also has rarity, you only need common salvage for common IOs, the uncommon and rare salvage is for set IOs (and costume pieces and temp powers).
Common: 22 in 28 chance (78.57%)
Uncommon: 5 in 28 chance (17.86%)
Rare: 1 in 28 chance of rare (3.57%)
Invention salvage also has ranges. Certain drops only occur at certain level ranges. Examples:
Ancient Artifact (magic common salvage) only drops from mobs of level 4 to 25, with the bulk of it dropping from 4 to 19.
Masterwork Weapon (magic common salvage) only drops from mobs of level 20 to 39, with the bulk of it dropping from 26 to 35.
Nevermelting Ice (magic common salvage) only drops from mobs of level 35 to 54, with the bulk of it dropping from 40 to 54.
Great, I have a recipe and the required salvage, how do I invent something? You need a invention worktable. These can be found in the universities in Steel canyon, Croatoa, Founders Falls, and Cap au Diable. Also, if you have access to a supergroup base, the base designers can add a invention table to the base. It works identically to the tables found in the universities.
Wait a sec, after I go through all this I still have to pay? Yes, you still have to pay a fee to the table. Do not blame me, I didnt design the system.

The upper level IOs seem expensive (and they are) but they are better than any SO you can get in the game.
The Goodies
OK, how much better? Paragon wiki has a
table, but Ill hit the highlights. For common IOs (the ones that only enhance one aspect of the power, similar to existing TO/DO/SO), there are several interesting levels. I am going to use examples from category a and b (the devs use 4 categories to define enhancements. A is damage, accuracy, recharge reduction, health, and many others, these all give 8.33 as a TO, 16.66 as a DO, and 33.33 as an SO. B is damage resistance, defense, to hit buff, to hit debuff and range, these all give 5 as a TO, 10 as a DO, and 20 as an SO. There are also schedules C [interrupt enhancements] and D [knockback distance], but they are less commonly used.)
[u]Level 15 IO:[u] This IO is always 19.2 for schedule a and 11.2 for schedule b. So, if you can access level 15 IOs, you would not need to upgrade them until you can get SOs or higher level IOs. Note: IOs dont combine, you cant add a level 15 IO to another level 15 IO, nor can you add them to combine them with any other type of enhancement.
[u]Level 25 IO:[u] This IO is always 32 for schedule a and 19.2 for schedule b. This is slightly less than an even level schedule a SO, 33.33, or an even level schedule b SO, 20.
[u]Level 30 IO:[u] This IO is always 34.8 for schedule a and 20.9 for schedule b. This is slightly better than the equivalent green (single plus) SO.
[u]Level 50 IO:[u] This IO is always 42.4 for schedule a and 25.5 for schedule b. This a level that SOs cannot achieve. Note though that ED applies to IOs just like any other enhancement, so slotting more than two IOs of this level has drastically diminishing returns.
Oh I heard there are new costumes! Where can I get them? The new costume items are pictured on
Paragon wiki costumes. They are invented, you must get a recipe drop and the required salvage. Currently the recipes are selling for insane prices (tens of millions down from the first weeks hundreds of millions). You must craft the item on the character you want to use the item on. Do not get everything together with your main and craft it, intending to give the result to an alt. Whoever clicks the craft button gets the costume unlocked. As is typical in CoX, the costume is granted to a specific character, not to an account. So if you want your level one alt to have rocket boots, you need to acquire the recipe, the salvage, and the inf and transfer all that to the character. Then that character goes to an invention table and crafts the item.
Well, that sucks. Yes, yes it does. If you are hoping for a costume drop, your best chances are on a low level (10 to 19) or high level (43 and up) character. The reason for this is the costume recipes are classed as uncommon class a (mob only) drops, and those two level ranges have the least number of uncommon IO recipes. For a detailed analysis of why these particular levels go
here. Note that everything that pertains to costume items pertains to the inventable temp powers as well.
What about all these set bonuses I hear about? This is explained very well in this
guide on the CoH board. Also, Scrapulous from the CoH boards has done some excellent examples of set IO slotting:
Health
AoE holds
Melee attacks
Planning builds for set bonuses
Sample fire/fire tank build
Example dark melee/regen scrapper build
The Markets
(Much of this is explained on the
Paragon wiki Consigment houses)
You keep mentioning Wentworths/Black Market, what are they? Wentworths is the consigment house for heroes, Black market trucks are for villains. They are in the following zones and are indicated on the in game maps:
Atlas
Kings Row
Steel Canyon
Talos
Mercy
Cap au Diable
Sharkhead
St. Martial
This is where you can buy and sell stuff. Inspirations, base salvage, Halloween salvage, regular enhancements, hamidon enhancements, and invention stuff can all be sold (and bought) at Wentworths. The catch is all the stuff is sold by players, so you never know what is available. Note: the Black market is totally separate from Wentworths, however they both span servers. Wentworths, and the Black market, show listings from every US and European server. So there is no such thing as the Virtue Wentworths, its Wentworths for all servers. Also, the test server has its own unique Wentworths/Black market.
How do I place an item for sale? You click on one of the friendly Wentworths NPCs (or the surly black marketers). [There will be a pause as all the data loads into your PC. This pause can vary from several seconds to over a minute, depending on your PC. A good indicator of how long it will take for the buy/sell screen to open is the length of time it takes you to zone: quick zone means a fast loading, slow zone means a slow load. This is because the server is sending your PC all the information about each and every item for sale.] Once the interface opens up, you will see three panels. The upper left is a series of lists of item categories. The right hand panel is the actual items for sale. The bottom panel is your sell/order slots. You have ten slots initially that can be used to buy and sell. You could have 10sells and zero buys, 5 sells and 5 buys, or any combination of ten pending transactions. You gain aditional slots buy gaining levels and gaining badges from making sales on the auction house.
To sell something, you drag it from your inventory (the salvage screen, recipe screen, enhancement slots or inspiration slots), onto the transaction bar (the bottom panel). A prompt appears asking for you to enter a price. If you are unsure how much to ask, you can use the upper left panel first, to look for the item you are selling. Once that item is displayed in the right hand panel, you can click on it, and it will show the prices of the last five transactions. This is the only time you will ever see buy/sell data for other players, and even then it is just the prices, no player information.
To buy something, use the upper left hand panel to look for the category you want (inspirations, recipes, salvage, etc), and click on that item. This will filter the right hand panel to show items of that category. Scroll around until you see the item you want to buy. Click on that item and it will expand to show information about the item, including the last five prices paid for the item. There is a field to enter the price you want to pay. Note that the buy list is very specific, a level 10 recipe for Numinas Delicate Unmentionables is not the same as a level 11 recipe. If you want to put offers on a range, say all the Numinas Delicate Unmentionables recipes from level 10 to 15, you actually have to enter six different buy orders.
OK, so how does the buying/selling actually work? Sellers set a minimum price (in influence/infamy), but no one can see that price but the seller. Buyers post a buy order for what they think an items is worth, again, no one but the buyer can see the price. When a player places an item for sale, there is an order of events:
Check to see if there are any buyers
If there are buyers, check to see if any are offering the asking price or more
If multiple buyers meet the asking price, the item is then sold to the highest bidder
Sales are always matched with the cheapest item going to the highest bidder. So, if you put a level 1 accuracy TO up for 10 inf, and there are three buyers looking for a level 10 accuracy TO:
One buyer is offering 50 inf
One buyer is offering 1 inf
One buyer is offering 1 million inf
You will get approximately 900,000 inf. Why 900,000 instead of one million? This is a consignment sale, the house (Wentworths) skims about 10% off the transaction. There is also a posting fee of about ½ a percent of the asking price (minimum 5 inf). This fee is refunded to the seller if the item sells. However if you pull the item from sale before it sells, you lose the posting fee. Why would you pull an item? Maybe you realized you placed too low a minimum, in that case if the item didnt sell immediately, you can place it back in your inventory, then repost it with a higher price. On the other hand, maybe you thought the widget of wonder was going to sell for 50 million inf, but the market crashed (say the devs reworked a power and the widget no longer is deemed useful). Now widgets are selling for under 10 inf. Three months later your 10 million asking price is still unmet. You decide to pull it to free up a transaction slot. You wont recover the approximately 50,000 inf posting fee you originally paid to place the item.
I placed a buy order three hours ago, how come I havent gotten anything? Any number of reasons:
There are none for sale
There are none for sale at less than the price you are offering
There were some for sale, but other buyers made higher offers
What happens when I log off? You sales and buy offers are maintained by the consignment server. If a buyer (or seller) comes along while you are sleeping, the transaction will occur. When you next log that character on (note this is by character not account), you will see a notices that you have sold (or bought) an item(s). Head to the nearest Wentworths and collect your booty (inf if you were selling or the item you were wanting to buy) by clicking on one of the helpful staff. The consignment window will open and the transaction panel will have SOLD or BOUGHT over the item. Clicking on that item gives you the option to collect it. Note that you must have a free slot of the appropriate type available to collect any items that you have bought.
((in comments, please remember this is a high level beginners guide, I do noy intend it as an exhaustive guide to set IOs, or gaming the market, or where to hunt for drops.))