Avoid Death is a High-level class ability available to thieves and bards.
In-game description 
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| “ | Avoid Death With extraordinary effort, a high-level rogue can avoid almost certain death. The effect lasts for 5 rounds, and during this time, the rogue's Save vs. Death receives a bonus of 5, Hit Points are increased by 20, and the rogue becomes immune to death magic. | ” |
