Curse of the Horned One
As with Undead and Chaos spells which summon new models you may only transform victims into Skaven if you have models to represent them. Skaven created by this spell will be armed with a hand weapon, light armour and shield, but the models may show some variation as normal.
All Skaven transformed by the spell are arranged into a separate unit adjacent to the enemy unit they were transformed from and in hand to hand combat with it. Both units may rearrange their formations as convenient, but neither may increase its depth compared to the original target unit. No blows are struck until the next hand to hand combat phase and neither side counts as charging. Once models are transformed they cannot be changed back by a subsequent Dispel or Drain Magic; the effect is permanent. Note that the Skaven sorcerer does not have to be able to see his target to use this spell.
Plague
Although the plague inflicted by this spell is magically induced it does not affect undead or daemons. It is a real, physical plague, although an extremely fast acting one!
Poison Wind
The Poison Wind eats flesh and bones like acid so it will affect even unnatural creatures like undead and daemons.
Death Frenzy
This is the most devastating spell in the Skaven repertoire. The enhanced abilities are all resolved in the appropriate phases. The spell merely confers the extra speed and attacks, it does not move the unit affected or enable it to strike. Combined with Skaven's rat-quick movement rate it enables units to charge 20" or more and then fight with double their number of attacks.
The spell remains in play, and cannot be recast until the magic phase after it has been dispelled or taken back (as normal for spells which remain in play). Note that wounds suffered from over-exertion are rolled at the start of each magic phase and therefore before the Grey Seer has a chance to take the spell back. This means units which are in Death Frenzy will always suffer 1D6 wounds at the start of the magic phase.
Madness
Madness works just like the Grey Magic spell Traitor of Tarn, so the victim cannot be forced to kill itself, throw away its weapons etc. It is possible to force the victim to fight models from its own side. This spell remains in play and the card is left face up either on the table or somewhere where it can be seen.
Scorch
Burning terrain can be marked with cotton wool if desired. Each time the fire spreads to another piece of terrain it starts a new fire and each fire is rolled for separately at the start of the Skaven turn.
Burning buildings will sustain 1 point of damage at the start of each player's turn as stated in the Warhammer rulebook. Models get their normal armour saving throw against wounds caused by this spell. Note that the Skaven does not have to be able to see his target to use this spell.