- Plans: Corruption
- Requires Blacksmithing (290)
- Item Level 58
- Use: Teaches you how to make Corruption.
- [Corruption (sword)]
- Requires 40x[Thorium Bar], 2x[Arcanite Bar], 16x[Demonic Rune], 8x[Essence of Undeath], 2x[Blue Sapphire], 2x[Dense Grinding Stone], 4x[Rugged Leather]
- 1 Charges
- Sell Price: 55
Source
These plans are picked up while opening 
[10-50] Blacksmithing Plans while in Stratholme. The plans are near the second ziggurat, at [79.1, 45.6].
Taking these plans summons a Black Guard Swordsmith. This skeleton must be defeated to complete the quest Corruption, as part of the requirements to gain the swordsmithing sub-specialization of Weaponsmithing (Blacksmithing).
As of October 06 2008, this item had been confirmed as broken by several in game technical assistance operatives. [Plans: Corruption] had not dropped from the [10-50] Blacksmithing Plans in Stratholme or anywhere else since the removal of the Weaponsmithing quest lines at the advent of the Burning Crusade. There was no proposed intent to re-introduce this item into the game, however the item began dropping again after the 3.0 patch.