The concept, and execution, is borne entirely out of watching the community extend the life of previous iterations by challenging each other to kill specific NPCs not related to either story of that mission's objectives in as creative a way as possible. IO took the idea, painted a potential target on everyone's head, and built a new additional gameplay mode out of it.
Standard missions can be replayed in Contract mode - an ongoing, global challenge list created and sustained by the community, with the top five each week highlighted by the studio within the game's online side. In any level you can mark up to three targets, take out each in turn, and exit the level. The game immediately records the who, when and how of each and uploads that run-through as a challenge for other players to try and match and beat - with a timer running down as soon as you score your first hit. Better that time, and increase the score with a kill with flair, and you'll enter up the online leaderboard.
IO didn't detail whether there was potential to effectively one-up friends and have the new tallies upload as the new challenge bar to beat, and at bare basics the idea could be too easily cooked if gamers aren't imaginative. But the mode calls for imaginative kills, tough contracts, so other players are left with a level-sized puzzle and one question: "how did they manage that?"
IO demo the very first reveal again, as 47 tries to escape a library full of cops, except this time they need to kill a Sergeant who's dug into the centre of the group like a tick. Well-lit and well-protected, it means you have to approach the stage with a wholly new set of tactics in mind.
The team walk us through a later level as they set up a Contract: this is no separate Editor, no God mode -you set the perimeters by your skill alone. It means every Contract is solvable - almost like a Trials level in a way.
The team recorded over two thousand pages of script for the game, and it'll best be shown in this mode as you spend more time listening in on people's conversations, and their lives, than you would with some of your extended family. IO is building extra extensions within the pre-existing framework of the game, and the potential of extending its life is lead by the community's existing enjoyments: no awkward social network extensions, no crowbarred modes alien to the series - it's up to the players to make what they will of the tools at their disposal.
We'll be talking to the team about this new mode at Gamescom, so keep checking back with the site for a GRTV Interview in the very near future.