The basics of mission design are pretty simple. Architect Entertainment buildings are located in most areas across the Paragon City for Heroes and the Rogue Isles for Villains. Consoles allow access to creation tools where users put together missions and string together a series of them for a story arc. Putting a basic mission together is fairly simple: You need a contact, a setting (map), enemies and end goal(s). Characters can be custom built using the game's famous character creator. Once everything is in place, players fill in the relevant lines of text to tell a story. Players can then test the missions to make sure everything works as expected, and then publish their works to be shared with everyone in the game. Other players can then play through, rate and comment on customized missions.

Although the Mission Architect is a powerful tool for bringing stories to life, there are a few limitations to keep in mind. The most challenging is the 100 KB memory limit each story arc must adhere to. Although it sounds like a very small amount of space, it's possible to pack in quite a bit of gameplay into it. Every event and little bit of text takes up space, but nothing eats up memory space more than using custom created characters. Users can conserve a lot of space by using in-game characters whenever possible, but that comes with its own set of limitations. Built-in characters and minions cannot be manipulated outside of assigning them to a player-made group and renaming the major bosses. Enemy types determine the level range of the mission, and entering players will either have their levels scale accordingly or they won't see ineligible enemies. Players can't select a particular enemy based solely on looks or abilities hoping to fit it into the story. In a sense, the Mission Architect encourages players to use built-in characters while at the same time forcing them to create unique ones to fill certain needs.

Another difficulty we encountered was scaling the strength of some of our custom-made boss characters. The Mission Architect tool doesn't allow players to choose specific powers for their characters. Players select primary and secondary power sets and choose between standard, hard or extreme settings to determine what powers the characters will have access to. The character's rank (minion, lieutenant, boss, etc.) also impacts damage output and determines the character's toughness. It's possible to mix and match between archetypes, so players can design a Blaster/Tank or a melee fighter with its own support powers. Epic class abilities like Kheldian transformations and general Pool Powers are unavailable. Oftentimes, our custom made characters came out either too powerful or too weak. It's easy to insert your own character into the story - the character creator lets you import it directly - and it's natural to want to see it be a powerful ally fighting alongside players. However, even at its lowest setting, an Elite Boss ally can pretty much destroy everything short of an Arch-villain, and the mission ends up playing itself. Similarly, it can be very difficult to find the balance between creating a challenging boss to fight and a near impossible one.

The other half of the fun comes from playing people's custom missions and having others play yours. Although the custom mission comes up as a Task Force, new players are free to join midway through. These encounters earn experience, debt and influence just like regular missions along with special badges, but players also earn "tickets" that can be traded in for rewards and unlockable content for the Mission Architect. Unfortunately, there's no way to promote your creation in-game except by broadcasting messages in hopes of someone joining in. The Mission Architect allows users to browse and sort through a list, but it's a huge list. It's hard to see how users will discover and rate story arcs within the sea of content. There's also no way to bookmark favorite missions or authors. Players are only allowed a maximum of three published stories and can unpublish stories when necessary, but doing so will lose its ratings and unique ID number. So unless one of the missions gains enough popularity to be moved into permanent storage, it's hard to keep a story out for long-term discovery while working on others.

Despite its shortcomings, the City of Heroes Mission Architect gives players unprecedented control over the kind of content they want to see and experience. That feat more than compensates for the difficulties we experienced. If you're a player that left City of Heroes after playing through all the content, this is an excellent reason to return. Active players have a means of making Paragon City and the Rogue Isles a world of their own.