The June, 1997 issue of "Next Generation" magazine featured an interviewwith Roberta Williams and Mark Seibert, respectively designer and produceron Sierra's forthcoming King's Quest: Mask of Eternity game. Next Generation:  Do any of the puzzles [in Mask of Eternity]have multiple solutions? Williams:  We thought about doing that but decided not to. Seibert:  When we first started the design, we talked about multiplesolutions and multiple paths.  The more we talked about it and themore we researched it, we learned that especially with adventure gamesonly about 13% of the people who play them actually finish them. [Laughs]  Then it was like, why do we want to make all these multiplepaths? Why indeed.  It seems, however, that Seibert and Williams have reallymissed the boat on what non-linearity in computer games, adventure gamesin particular, is all about.  Despite the fact that Mask of Eternityis supposed to feature a "hot new 3D engine," it would appear that Williamsand Seibert still hope to constrain the player's options to playing oneset-in-stone storyline, where there's only one solution - in any givensituation - which you're "supposed" to perform.  Any attempts at alternatesolutions to given situations, regardless of how clever, will result infailure.  How is this interactive, again?   I feel that the point of computer games, again with adventure gamesin particular, is to present each player with an experience that is relativelyunique to them.  That is to say, the computer reacts to the choicesthe player makes, and creates an experience that, ideally, only they willhave.  Sadly, many story-centric adventure games such as (by presentindications) Mask of Eternity, don't really create a gaming experiencewhich is unique to the player.  When different players talk aboutthe adventure game they've both just finished, the difference in theirexperience will only be where they got stuck in the game, not in how theysucceeded at it.  For in order to succeed in the linear adventuregame, they must have made the same decisions at each juncture to have finished. In the end, each player will retell the exact same story of "his" adventures. Is this interactive? Whaddaya Mean, Non-Linear? Non-linearity doesn't just refer to storylines, it refers to the typeof gameplay involved.  In a constrained adventure game such as Maskof Eternity, only one path will lead to success, and only one style ofplaying the game will allow the player to finish.  It's linear. In a non-linear game, the player can succeed in many different ways, hopefullyenough different ways that each player's gaming experience will be uniqueto them.  Different types of computer games are non-linear to differentdegrees and in different ways.   Though the term is most oftenapplied to role-playing or adventure games, arcade games or strategy gamesare non-linear in their own way.  For instance, in a classic arcadegame such as Centipede, each player is able to succeed using differentstrategies, ones she develops herself while playing the game repeatedly. The objective remains the same:  to destroy the downward-moving centipedesand other enemies, so as to survive as long as possible while achievingthe highest possible score.  Different players will develop differentmethods to achieve this same end:  some will meticulously shoot atthe mushrooms on the play-field so as to maintain an obstruction-free spaceto survive in, while others will concentrate all their efforts on the movingadversaries on the screen.  Other players still will go for the non-threateningbut high-point-earning scorpions which traverse the top of the screen.. Still others will come up with their own strategies for success. And all these different methods can still lead to a player gaining thehighest score at their favorite arcade, hence (in some ways) "winning"Centipede. For all intents and purposes, Damage Incorporated is a sophisticatedarcade game, and as such is "non-linear" in that their are multiple strategiesthat can all lead to success.  Though the objectives vary from levelto level, your goal is always to finish the given area so as to progressto the next one, and this primarily involves "eliminating" a lot of "hostiles." However, this eliminating can be accomplished through many different strategies,with differing levels of success coming with the different tactics. Some may sacrifice their teammates so as to avoid personal injury, whileothers keep their squad alive at all costs, dying themselves many timesin the process.  Both can still finish the can game. But it Isn't Totally Non-Linear   However, Damage is linear in that you can only play the levels in theorder they're assigned to you.  Furthermore, the game can really only"end" two ways:  you die, or you defeat the enemy forces utterly. Your actions in the game have no actual impact on the storyline that accompaniesthe levels, and it will always unfold the same way.  In this respectDamage, as well as the entire Marathon series, is extremely linear. But since the game is primarily an arcade game with a story provided aswindow dressing, this is somewhat acceptable.  The player has theirown unique game playing experience through developing their own strategiesfor completing the levels.  As such, when two buddies who've bothcompleted the game discuss it, their conversation may go something likethis: Liz:  Woah, wasn't that great at the end of Damage Incorporated,when Jeremiah says all that weird stuff? Max:  Yeah, it was, I remember that.  But boy, that lastlevel really was hard though, huh? Liz:  Dude, no way!  I'll tell ya what I did.  I setmy teammates on Hold Commands, and then instructed them to....  See, it's easy. Max:  Wow, I never thought of that.  Maybe I should playit again... In this way Damage's non-linearity encourages Max to go play the game again. But, more important to me, Liz and Max had different experiences playingthe game. Whereas Liz rocked through the last level without difficulty,Max got his butt handed to him many times before barely finishing the game. Max felt less accomplished in his skill and thereby less happy, whereasLiz felt on top of the world since she breezed through the ending so effortlessly. Adventure Games are Another Ball 'o Wax With adventure games, however, making the storyline non-linear is theonly thing that will make different players have experiences unique tothem.  With a linear storyline the designers force the user to follow,the player's creativity is actually discouraged, as only one solution willwork for a given puzzle.  It's very hard to find examples of situationsin "real" life which have only one solution:  there's almost alwaysmore than one way to accomplish a given goal.  Agreed, some pathsmay lead to greater degrees of success than others, but they're all solutionsnonetheless. A popular way of making adventure games non-linear is to allow the userto approach separate puzzles in whatever order they prefer.  Thatway, if a user gets stuck on one, he can go on to others, perhaps comingback to the troublesome puzzle later on.  Though the puzzles staythe same and still may only have one solution, at least the player is lesslikely to get frustrated by one puzzle and forsake the entire game. Still, is the player really getting a unique experience if they can simplyreorder the challenges however they prefer?  In some ways yes, insome ways no.  Technically such a game is non-linear, but really gamedesigners should try to not only allow the player to accomplish differentgoals in whatever they want, but also allow them to solve those differentproblems in a variety of different ways. A Good Example, if I Do Say So Myself My own Odyssey - The Legend of Nemesis I feel is a good example of howan adventure game can be non-linear.  Though technically a role-playinggame, I consider Odyssey more of an adventure-RPG hybrid, as combat isin many ways downplayed while finding solutions to puzzles is encouraged. But nearly all the puzzles in Odyssey have multiple solutions.  Whenthe player encounters a group of power-mad priests repressing their parishioners,the player can either sneak about and kill the priests, or she can extinguishthe source of their power, neutralizing the priest's control over theirfollowers.  Both eliminate the problem of the priests, but the ramificationsof the player's choice has an effect on the storyline of the game. Furthermore, Odyssey allows the player to pursue different problemsin whatever order they want, and doesn't even require the player to completeall the puzzles they encounter.  There are three ways to get to theend-game section, and from there different actions will lead to four differentendings, all of which have their good and bad points.  In additionthe game includes many, many sub-plots which the player can pursue or notat their leisure, depending on how deeply they want to investigate theworld presented in Odyssey.  The sub-plots will prove helpful to theplayer in that they provide him with additional skills and magical itemswhich may make combat easier, but they are by no means necessary to finishthe game. In conclusion, the point isn't to see how we can get the player to replaythe game, but rather to make each player have their own unique experience. Furthermore, Mr. Seibert's statistic that only 13% of adventure game playersactually finish a given game, points out that maybe the reason they don'tfinish is that they get stuck on puzzles which have only one solution. They look at the puzzle and say "well, if this were real life I could easilysolve this by using the widget from over here on that."  But sincethat solution isn't the one the designer had in mind, and since the designerdidn't bother to take into account the player's creativity so as to allowfor multiple solutions to puzzles, the player gets frustrated and quits. Self fulfilling prophecy, anyone? This column was originally printed in InsideMac Games.