Rare loot (Origins)

Dragon Age: Origins and Dragon Age: Origins - Awakening use a unique system for distributing loot and balancing gameplay. Creatures maintain two potential inventory systems, an equipped inventory, and a dropped inventory. The former controls the appearance of the NPC's model (for example armor, weapons, etc.) whereas the latter controls the loot yielded and available to the player upon looting the NPC's corpse.

Rare Loot Explained

In both games there appears to be a small, unparsed % chance of a creature/npc to drop one of more items in his equipped inventory when killed, causing the generic dropped loot table to be dropped, along with x-item from their person. In many cases this results in a piece of generic armor, or a generic weapon. However, occasionally this can result in rare magic items, or even unique magic items not found anywhere else.

Item Number Chance
One-Hit Kill	Critter	Weak Normal	Normal	Lieutenant	Boss	Elite Boss
0.0%	0.25%	0.4%	0.5%	1.5%	2.5%	3.5%
Equipment Chance
One-Hit Kill	Critter	Weak Normal	Normal	Lieutenant	Boss	Elite Boss
0.0%	0.0%	0.02%	0.05%	0.2%	1%	1%
These numbers are taken directly from the resource game files.

Notable Drops in Origins

Notable Unique Items

• Sophia Dryden - Warden Tower Shield
• Adventuring Mage - Robes of the Gifted
• Gaxkang the Unbound - Fade Wall

Notable Rare Magic Items

• Lightning Rod - Dropped by casters
• Executioner's Helm - Dropped by melee fighters
• Chasind Crusher - Dropped by Qunari Mercenary in Deserted Building (possibly any Qunari wielding a hammer)

Notable Drops in Awakening

Notable Unique Items

• Smuggler Leader - The Felon's Coat / The Rose's Thorn / Spear-Thrower / Gloves of Guile
• Crow Assassin (Burning Bridge) - Wolf Treads / Backhands / Blackblade Tunic / Fang / Dumat's Claw
• Crow Assassin (Vigil's Keep - Throne Room / Old Stark's Farm) - Vest of the Nimble / Imperial Edge / Antivan Leather Boots / Wade's Drakeskin Gloves / Crow Dagger
• Apostate mage - Vestments of Urthemiel / Enchanter's Cowl / Elementalist's Grasp
• Adria - Noble Clothing - female only - blue and purple gown with red trimming. There are many different types of noble clothing in Dragon age, this is the only one Adria drops.
• Rylock - Landsmeet Shield / Knight Commander's Plate / Templar Gauntlets
• Utha - The Winter Blade / Dwarven Massive Armor
• Avvar Lord - Ser Alvard's Sword / Dwarven Massive Armor / Greaves of the Sentinel / Duty
• Third Disciple General - Sage's Fuzzy Head-Sweater

Notable Rare Magic Items

• Various "Blood Mage"s - Skins of the Keeper
• Various casters, including Hired Goon Leader - Lorekeeper's Robe
• Lieutenant - Ceremonial Armored Boots / Helm of the Red / Maul / Ceremonial Armored Gloves / Ceremonial Armor

Notes

• The % chance of possible equipped item drops is extremely rare (≥1%).
• The chance the equipment from the equipment slots you can get is in fact the "unique item" is also low: 1/6 (up to 6 possible equipment slots, NPCs do not tend to have belts, amulets or rings equipped—this is not including guaranteed drops from their inventory).
• If the above system is in fact correct, then the previously accepted theory of increased drop rate in Nightmare mode (due to reduced drop rate of potions) is incorrect.