Why should multiplayer gamers have all the fun? That's part of Bungie's pitch for its ambitious "Player Investment" system being implemented into what could potentially be the studio's final Halo adventure, Halo: Reach.

It's been a while since Bungie had a chance to reinvent their brand of online play and Player Investment is Bungie's response to the more RPG-influenced level-based multiplayer experiences found in dominating games like Infinity Ward's Call of Duty: Modern Warfare 2. Whereas Modern Warfare 2 and its ilk confine these experiences to multiplayer, Bungie's hoping to rope all of its Halo fans under a single, player-driven umbrella and involve single-player.

"Whatever your preferred flavor of Halo is, we're gonna find a way to reward you," said Bungie player investment designer (and former games journalist) Luke Smith in a phone interview with me earlier this week. "Whatever you enjoy doing in multiplayer, we're gonna find a way to reward you. Through the Player Investment system, you're going to be building an identity for the first time in a Halo game."

Bungie has detached Halo 3's ranking from the Trueskill system that drives matchmaking. Previously, the on-screen ranking users saw reflected how players would be matched up competitively, meaning someone with a high ranking would most likely be a competent Halo 3 player. That's not necessarily true in Halo: Reach. To be clear, Trueskill is still driving matchmaking, but Player Investment is more reflective of the amount of time someone's dedicated to Halo: Reach and not necessarily their skillset. Someone can have a high Player Investment ranking and be a terrible player. But since Trueskill is tracking that data in the background, away from users, it will still match players appropriately. So, don't worry: terrible Halo: Reach players will be matched with other equally-awful Halo: Reach players.

Player Investment is driven by credits ("cR" for short). Credits are given to gamers simply for playing Halo: Reach, either through rounds of multiplayer or by working through the single-player campaign, but the amounts of credits vary, based on the actions of the player. Different actions will dole out a different amount of credits, but Bungie is being careful to not encourage player actions that would potentially damage the gameplay experience. It does mean that more challenging tasks (say, five headshots in under a minute) would produce more credits. Bungie's currently balancing how credits are doled out, but credits drive the Player Investment experience, both to increase a player's Military Rank (replacing Halo 3's Ranking system) and to purchase customization items in Halo: Reach's "Armory."

In Modern Warfare 2, as a player levels up, they unlock new abilities, new weapons and other features that fundamentally change the gameplay. Someone who is level one in Modern Warfare 2 can not equally square away against someone nearing the level cap. Bungie is being mindful to avoid that type of player inequality in Halo: Reach. Everything that players gain access to via credits in Halo: Reach are used solely to purchase helmets, shoulders, chests and other accessories that allow Halo: Reach players to create a Spartan who is uniquely them. These items are for visual changes only and do not affect the flow of gameplay.

"There are no in-game benefits to Spartan armor," said Smith. "It would definitely make Halo something different than what Halo is."

This player uniqueness is reflected in multiplayer and single-player. Your customized Spartan having battles in multiplayer is the same Spartan you're controlling while fighting the Covenant for control of Reach in the prequel storyline. Bungie wanted Halo: Reach's story to be more about the player's role in the battle, rather than simply assuming control of Master Chief and guiding his actions. Your customized Spartan is even included in the cut-scenes.

"When the cut-scene comes up in campaign, we want you to see you," said Smith. "For instance, that trailer that we showed with the helmet and soldier picking it up, the Noble 6 trailer, that helmet is going to be your helmet. If you're pink and adorned with unicorns, that's how you're going to look. [...] With Reach, this is your story, this is your identity, this is your version of a story that we want you to be a part of."

In speaking with Bungie, Smigh pegged me as someone they are targeting with another new feature called "Challenges." Smith knows me. He understands I'm not the most skilled Halo player and am more likely to finish the single-player, maybe dabble in multiplayer, get frustrated because most players are better than I am and move on. Bungie's hoping Challenges will keep players like myself coming back for more. Challenges come in two forms -- daily and weekly -- and are Bungie-developed obstacles that provide short to medium-length goals to be achieved solo or with groups. As Bungie expects most gamers will tackle Challenges after spending a chunk of time with Halo: Reach, many Challenges will have a notable difficulty curve.

"Some of [simpler daily challenges] are aggregate actions," said Smith, "like kill X dudes, help kill X dudes today. Sometimes those dudes we want you to kill are gonna be in multiplayer, [or] they're going to be in another mode. Sometimes it's going to say just kill anyone anywhere, we don't care what you do, just kill people and we'll reward you for that."

Smith knows what kind of Halo player I am because we've played Halo together. But it's hard to know exactly what kind of player someone is just by looking at their user profile. An impressively high rank doesn't tell you anything about their play style. Bungie hopes to help alleviate that problem with "Commendations," described as persistent medals that reflect player actions over an extended period of time. For example, if the game tracks that you spend most of your time battling with a sniper rifle, your Commendations show that. The profile can eventually represent a snapshot of your Halo play style and provide a better understanding amongst friends and strangers where player strengths are. Oh, and along the way to earning Commendation medals, you'll of course be earning credits.

"There are guys [who] just want to drive people around. We haven't done a great job of reinforcing that kind of behavior in the past"

"I can look at your service record, Patrick," explained Smith, "and see that you have a ton of assists and a ton of progress in your wheelman Commendation, so I know that you like to be a support player, you like to drive vehicles. That's your preferred style. One of the things that we really want to do a better job with Reach is [highlighting] the guys out there who do like their Halo maybe differently than, for instance, I like mine. I like head shots, I like killing people with a sniper rifle, I like all that stuff. But there are guys that we've encountered along the way who just love to drive; they just want to drive people around. We haven't really done a great job of reinforcing that kind of behavior in the past and the Commendation system is one way we're doing that."

Bungie's ambitions for Player Investment suggest hopes for a more efficient, more persistent player experience that extends over users' single and multiplayer adventures. While some gamers might hope for customizability that extends beyond the visual appearance of their Spartan, that's not Halo's style. But if you burned with jealousy over a friend getting their hands on Halo 3's Recon armor, well, Bungie has a whole new set of tools to play with. And for someone like myself, maybe there's a reason to play multiplayer again once the credits roll.

Halo: Reach's multiplayer beta goes live May 3. The full game will be released later this year.

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