Sony's Copycat Policy
Japanese Invasion

The Cost of Inventories

Inventory We are finally seeing a movement towards relegating inventories to secondary status in mass market games, a move that I believe is helpful to increasing the appeal of games - case in point, games such as Halo and Mercenaries which allow the player only two weapons, or Rogue Trooper, which allows its single weapon multiple roles. While any game rooted in the traditions of role-playing games is likely to maintain an inventory, these are gradually adapting to their new role as a mechanism of interest chiefly to the (increasingly large) minority audience of game-literate players.

I am not against inventories - they make sense for games in which planning an expedition is part of the play (many but not all role-playing games), for games using plenitude of objects or clues for puzzles (adventure games), for any game in which logistical play centred around trade is key (such as space trading games a la Elite, or various other kinds of role-playing games) and for any game wishing to create tension by providing strict limitations (survival horror games, for instance). But I do not believe that inventories are necessarily a good idea for an audience with low game literacy, such as the mass market audience in general.

I increasingly believe that the single largest barrier to wider audience is steepness of learning curve, and that the largest single factor in this is dimensionality of control, that is, the complexity of the interface.

There are two particular costs to inventories which hurt mass market appeal:

1. They add to learning curve. The player must learn a control to access the inventory, then (usually) learn a custom set of controls to operate the inventory.
2. They often add to dimensionality of control e.g. by adding +1 dimension for scrolling left or right through the inventory. This also produces very clumsy play from time to time, as players fumble through their inventory for the right weapon or tool!
3. They undermine engagement by forcing the player to switch between direct play and inventory management.

Remember, I'm not against inventories, I just think they are not helpful for mass market appeal. Superior solutions when dealing with a widespread audience include:

1. Context Sensitive Inventories

Project_zero_2_rigell_003 We already see considerable use of context sensitive use of items - such that the Action button will use the correct item in the correct context. The only example I can think of on the fly is the use of items in Project Zero/Fatal Frame, whereby each situation requiring an item automatically uses the correct item (if anyone remembers other games where the items are always used in a context-sensitive form, please jog my memory!)

This can become complicated at the design level, because it is necessary to ensure that the game contains no overloaded contexts. Still, better to give a complex probem to the game designers, who thrive on complexity, than to the players, who may not!

We could even see context sensitive weapon use, if we wanted to: enemy out of range, auto-select sniper rifle; enemy at far range, auto-select assault rifle; enemy at mid-range, auto-select SMG; enemy at close range, auto-select shotgun; friendly targets present, auto-select pistol; enemy too close for guns, auto-select melee. (This should be viewed solely as a preliminary suggestion for such a scheme, not an ideal case).

If there is potential for Hardcore players to be frustrated by not having direct control, an alternative control configuration giving manual control can also be provided.

2. One or Two-Slot Inventory

Contra_arcade_game Remember the classic arcade games, where you had a simple choice of which weapon to take (as in Contra, or in Nemesis/Gradius with the choice between three way or laser)? These games didn't need inventory controls, because they only gave you 'one slot'.

More common these days, we see a two-slot weapon inventory as with Halo, Mercenaries and presumably others. (Other citations in this regard welcomed!) These systems are fantastically efficient! They require only one control, and its function is clear (switch weapon). A context sensitive option to switch weapons for others that are found gives the player a choice of kit. It is an excellent balance point, especially when backed up with additional static functions (such as a grenade button in Halo, or the knife in Resident Evil 4).

In a multiplayer co-op situation, the limited weapon allowance permits each player to develop their own role. (When everyone is multi-role, the most competent player does all the work, while everyone else is relegated to practically spectator status).

3. Toolkit Inventories

Fotomontyontherun The idea here is the player does not acquire new equipment in the game, but tackles the play of the game with a fixed set of tools which are always available throughout the game (or throughout a particular episode).

We haven't seen this much in use, but this was an idea we were toying with for an atmospheric adventure game called 8, with Tale of Tales (the Endless Forest people - and note, the new version of this is out with a considerably more expressive interface). It is also reminiscent of the "Freedom Kit" used in the classic Monty on the Run (which was an early context sensitive toolkit), although a flaw in this case was that the player was very likely to pick the wrong escape kit and therefore be unable to complete the game - still, it was a tougher world for players in the 8-bit era!

This is an alternative to an inventory, but it doesn't solve the issues of inventory selection, per se. Perhaps it must be coupled with one of the two previous solutions to make it viable for a wider audience.


We will always have some games with inventories, but we are at last entering a time when player-operated inventory systems are being recognised as clumsy in respect of a wider game audience. Ironically, the 'new' inventory replacements have their roots in much older (8-bit) games, but delivered in shiny new games they seem refreshingly new. I have high hopes that in the near future we may see these ideas taken even further. Who knows what new replacements for the classic inventory we might see in the next decade?


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There are some very interesting issues surrounding inventories and their storied history in games, nice post Chris.

RE4 I think makes for a nice balance between satisfying both old schoolers and newcomers: given that accessing the inventory stops time, both parties will find themselves opening it often, if only for a little breathing room or to take a moment to select a new weapon after having sighted a terrifying new enemy--especially helpful for new players, who may not be as efficient at real-time weapon switching. Hardcore players of various stripes really seem to cling to the old-fashioned gridded inventory system for some reason. For me personally it has a lot of fond associations with other games that featured similar inventories, but also because there's a simple, neurotic joy to organizing your inventory in a pleasing fashion. Oh, and kudos to design team for having removed the ability to reload while in the inventory, though, as was possible in the RE4 demo :) That would remove a lot of important tension.

But let's talk about sequels with controversial inventory solutions, typically with the hardcore set: Deus Ex: Invisible War and The Eldar Scrolls: Oblivion. (Note: games with a colon and subtitle I think are far more likely to include elaborate inventories).

The first Deus Ex, which still stands as a compelling example of a hybrid FPS-RPG type, had a very traditional gridded inventory, as well as massively clunky interfaces for managing augmentations and other goodies. For the follow-up game, Invisble War, there was an unusual elliptical HUD design that incorporated the inventory management into a slot list on the left hand of the screen.

Now perhaps the biggest complaint, of the old fans as well as many of the new, was that the HUD itself took up too much screen space, instead of keeping itself in the corners like most. But the inventory was criticized as being far too oversimplified and too "console". I believe that the slot-based inventory system such as Invisible War could have worked with less problem, as it was a fairly elegant solution--the problem was it was a little too simplistic for the game it was incorporated in. Deus Ex players expected and enjoyed certain degrees of complexity, decision making, and organization--very logistically minded, in other words.

Invisible War's inventory committed some very serious sins: the slot-based system did not take into account item size or weight: a pistol, a sniper rifle, or a rocket launcher all took up the same amount of room in the inventory, which removed a lot of the strategy inherent to the first game, where taking a heavy weapon meant a huge sacrifice in inventory space. Of course, there was also the universally reviled universal ammo system: simpler for the designers and players alike to manage, but robbing their core audience with so much of the basic joys inherent with gunplay. The designers learned from all the ways that the first Deus Ex didn't port cleanly to a console, but in factoring in that experience into the second Deus Ex, they removed a lot of what made the game fun to a significant portion of their audience.

Oblivion's inventory, on the other hand, I think represents a much more successful compromise between PC and console, hardcore and newb-friendly design. Though once again hardcore RPGers are robbed of their beloved grid + paper doll system, Oblivion condenses a huge amount of information and object/skill management (inventory, spellcasting, skills, map, journal) into an interface that is easily navigable using an Xbox 360 controller, but also works well with a mouse. Items are automatically sorted into their respective categories in lists, and for armor and weapons simply clicking on them in the list will equip/unequip them. There is also a very sensible and handy pop-up for assigning a weapon to a quick-key (speaking of the PC version here, not sure about the 360 version). Now as always, PC players complain about the oversized fonts as an obviously console concession, but aside from that fairly minor criticism, Bethesda managed to create a very useable interface for what is one of the most complex games on the market. Bravo to their interface team.

I have this friend who seems to enjoy inventory management more than anything else. Watching him play WOW is an interesting experience. He will often spend hours in a city juggling and sorting his inventory until it is just right. Then he will go stock up on goods and start the whole process over again. After doing this for a few hours, he will log off. Then he complains that the game isn't fun. Go figure.

This is a great post, damn Chris, you crank out article quality work almost daily.

I'd already decided to abolish the traditional interface for Magic Circle, instead going for a context sensitive deal. If there are any props that are integral to the story they'll serve their function at the appropriate time. I'll be scripting out the dynamics of this, so I can probably manage to not overload contexts.

I'm also interested in the tool system you cite, I want to have more advanced magical functions enabled by a bit of alchemical goodness. Combining reagents, for example could involve a massive, clunky inventory, but I think I'll constrain it to a nice mini-game. I'm also thinking about having chalk and charcoal as two major commodities, one allows you to draw radicals at angle on the circle to set-up spells, the other allows you to draw an "anti-seal" over any seals you encounter to deactivate their magic. Either way, the real complexity of the game is accrueing the mental inventory of words you know that have magical function or social meaning, and its best to focus on that as the core complexity of the play. Good stuff, got me thinking.

Thanks for the kind words, Patrick! I don't set out with the intent of writing coherent articles, I just have a lot of material locked up in my head that I want to get out. On a good day, it all comes together usefully. :)

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