Third Generation Slann use up an extra Hero choice (so they take up a Lord and a Hero choice).

In addition to any other spells, they also know Drain Magic spell and have +1 wound.

However, Slann of the Third Generation are so ancient and revered that if one is killed in a game, the Lizardmen player's opponent gains 100 Victory Points added to his total at the end of the battle. If the scenario does not use Victory Points then the demise of the Slann has no effect.