The difference between Far Cry 4 and other Ubisoft Open World games is that while every action you take feeds into a seemingly never-ending cycle of rewards, as it does in Assassin's Creed, The Crew, Watch Dogs, etc, here it actually makes a difference to what you're doing moment-to-moment.
You're not just hunting feathers for the sake of it boosting an arbitrary number. Instead, actions are rewarded with a constant slew of upgrades that then enable you to be a more efficient murderer, which of course nets you more upgrades. A new Karma meter joins returning XP-based skill unlocks (now, thankfully, shorn of Magical Negro tattooing), where killing dudes cooly gives points to spend buffing offensive and defensive qualities, and complements the hunting-and-pruning of local flora and fauna that offers better ammo storage and chemical boosts.
