Epic wyvern poison

From NWNWiki

Initial effect: Lowers Constitution by 2 to 12 (2d6)
Secondary effect: Lowers Constitution by 2 to 12 (2d6)
Save DC: 26
Handle DC: 20

Epic wyvern poison is resisted upon contraction if the target makes a successful fortitude saving throw. If the save fails, the initial effect is applied, and one minute later a second saving throw is attempted to avoid the secondary effect.