http://blogs.halowaypoint.com/Headlines/...1712-.aspx
Famine - Weapons drop much less ammo.
Tilt - Enemy resistances and weaknesses are increased.
Mythic - Enemies have increased health.
Catch - Enemies are grenade happy!
Black Eye - Shields don't recharge unless you melee enemies.
Tough Luck - Enemies always go berserk, always dive out of the way, and never flee.
Iron - Co-op: Back to previous checkpoint on death. Solo: Restart mission on death.
Thunderstorm - Major upgrade to the capabilities of enemies.
Cloud - Motion sensor is disabled.
Cowbell - Acceleration from explosions is increased.
IWHBYD - Rare combat dialogue becomes more common.
Grunt Birthday Party - Headshot a Grunt, HAPPY BOOM TIME!
Blind - The HUD and the first person arms and weapon are hidden.
Im spoiler sind keine story spoiler drin, sonddern allerhöchstens gameplay spoilers.