Acheron
Acheron provides an easily readable glimpse into the cause of death for anyone in your raid or party.
Mists of Pandaria 
The Burning Crusade 
Wrath of the Lich King Addon Details
Expansion
Mists of Pandaria Categories
Developers
Having issues?
Acheron provides an easily readable glimpse into the cause of death for anyone in your raid or party. In addition to the damage and healing that occurred to someone up to their moment of death, Acheron also allows you to track and displays buffs and debuffs, which may also contribute to someone's death (Melt Armor on Al'ar, Corrosion on Felmyst, tank missed shield block, etc).
Right-clicking on a raid/party member unit frame will find a new option 'Show Death Reports'. Should be pretty self-explanatory from there.
/acheron show to show the main UI
/acheron config to bring up the config
Download Acheron
More addons for Mists of Pandaria
Discover other addons that might interest you
MogIt
In-game catalogue of items for transmogrification purposes.
Chat Loot Icons
Tiny icons for your lootz!
X-PerlUnitFrames
Replaces the normal unit, party, target, pet frames and adds target-of-target.
PitBull Unit Frames
PitBull is a Unit Frames addon that provides maximal customization.
EPGPLootmaster
EPGP Lootmaster provides a nice GUI for distributing loot and GP to the raid.
BigDebuffs
Makes it easier to keep track of target debuffs.
hcGossipBot
Automated interaction with questgivers and other NPC's.
DontCast
Warns when current target has buffs/debuffs that would reduce or eliminate the effect of damage