In Far Cry 2, your health bar is similar to those you've seen before. It's a horizontal line that fills from the left. It's divided into segments, but that we have seen before as well. This, however, is what gives us the first notably unique aspect of Far Cry 2's health system. These segments represent a hybridized version of the now standard recharging health system, popularized by Halo, and the old school health pack method. After taking damage and finding a moment to rest, your health will not recharge fully but, rather, fill the current segment. This means the hero is never totally helpless, with at-least some sliver of health, but also provides long term punishment for recklessness. This balance works well, satisfying both the game designer's love for the elegant and self contained recharging health and that segment of the gamer community that feels recharging health too contrived.
What really makes this system, however, is the way in which players begin to regain that health. Rather than damage being treated as if the player is a water balloon, leaking HP through his bullet holes, Far Cry 2 tracks actual injuries. If you get shot, there is now a bullet lodged in you. If you fall, you have a broken leg. These things really improve the immersion felt by the player and seem to make each injury feel more serious, without ever actually changing the risk/reward dynamic.
|This little piggy should have stayed home.|
In order to regain health, the player must treat these individual injuries. This requires removing foreign projectiles, dislodging terrain on which you have been impaled, stitching up gaping lacerations, resetting bones, etc. This becomes a really pleasing mechanic for two reasons. First, the injuries are very viscerally pleasing. You see the end of your finger come out the opposite side of your arm when you push a through and through out. You see flesh burning as you cauderize an open wound. You hear the crack of bone. It's simultaneously disgusting and spectacular. For the more squeamish players, I can see this being more motivation to keep their heads down than the threat of death. Compounding this, however, is the sheer multitude of animations and variants to these injuries. Quite some time will pass before you see the same animation again, which prevents these injuries from ever seeming trivialized and really adds to the verisimilitude of the whole experience.
Still less painful, however, than the rest of the game.
All in all, this system is a big winner for me more because of its psychological aspects than its objective ones. It provides that super soldier level of endurance necessary for a game in which the protagonist is expected to fend off an army on his lonesome, but never really makes the player feel superhuman. These constant reminders of your mortality and how hard the fight has been go a long way to contextualize the combat.
While I've seen no game sense which has copied this system, I will note a vaguely related piece of design in the Halo franchise. As of Halo: Reach, the players health no longer regenerates along with their shields, recalling the original title. This promotes a bit more caution in the player, as though they have little health it can be the difference between going down in 5 shots or 6. I've often noted situations in which taking the time to grab a health pack has saved my life. While this might not have been directly inspired by Far Cry 2, and was likely done more as an effort to return the series to its roots and maintain chronological canon, it does show an increasing popularity in this hybridized method.