‘The Witcher’: What Is the Spell Tissaia Used & What Happened to Her?

The sixth episode of season 3 of ‘The Witcher’ allowed us to see why Tissaia was so special as a mage, even when compared to the other mages of Aretuza. Called the greatest of the mages by Spymaster Dijkstra, it was clear that Tissaia had a lot of power up her sleeves when she turned the tide of the battle between the mages and the Scoia’tael through a powerful spell that wiped the battlefield clean. So, what was the spell that Tissaia used?

Tissaia used a potent and powerful spell called Alzur’s Thunder, which she used by channeling chaos through Aretuza and Tol Lara to summon thunder from the sky and reign down bolts of thunder down her enemies. However, as Ciri said, this was a spell of last resort due to the heavy toll on the mage’s body.

That spell that Tissaia used was proof that anyone needed to see to understand why she was such a powerful mage during her prime years. Also, by being willing to put her body on the line for such a powerful spell, she cared more about all of the mages than anyone ever did. So, with that said, let’s look at this spell in greater detail and talk about what happened to Tissaia after she used it.

Alzur’s Thunder is a spell of last resort

Many things happened in the second part of season 3 of ‘The Witcher.’ During that episode, we finally saw Vilgefortz showing his true colors by betraying the mages of Aretuza and allowing the Scoia’tael and the Nilfgaardians to enter by opening a door leading to Aretuza.

This led to a massive battle between the mages, elven warriors, and their allies. And because the Scoia’tael were prepared for the mages, this was a battle that Tissaia realized they could not win.

In that regard, Tissaia lost hope because she saw many of her friends and companions dying before her. She was also heartbroken that Vilgefortz, the man she loved the most, betrayed her and the other mages so that he could side with Nilfgaard. That was when she already had enough and decided to change the outcome of the battle using a spell that she had to use to protect her companions and her home.

Tissaia went to a balcony up in Aretuza and started channeling a spell through the entire building. Using her chaos, she could turn the sky dark as the nearby tower of Tor Lara started to spark as well. When Yennefer saw this from afar, she realized that Tissaia was about to use a spell called Alzur’s Thunder. And that was when Ciri remarked that this was a spell of last resort.

As Tissaia channeled the spell, thunder rained down from the sky and struck Tol Lara, acting as a lightning spear that channeled the thunder back to Tissaia. Using the power of the summoned thunder, Tissaia used her body as a conduit to release thunder bolts from her fingertips down to her enemies like how Emperor Palpatine does it. 

The spell was so potent that one strike could kill its target almost immediately. One mage even said that one look from Tissaia would allow thunder to reign down on that person, as it seemed like the spell worked almost automatically the moment that Tissaia had a target in her sights. This spell allowed the mages of Aretuza to gain a slight advantage over their enemies, as it was clear that the Scoia’tael weren’t prepared to deal with this power.

In the books, Alzur’s Thunder was a spell created by the legendary mage Alzur, who specialized in lighting-based spells. According to Yennefer in the books, Alzur’s Thunder is so complicated and powerful that only someone with the skills of Alzur could even stand a chance of casting it.

So, if the same holds true in ‘The Witcher’ series, that means that Tissaia was indeed the strongest out of all of the mages of Aretuza because she was the only one capable of casting this spell.

But how she used the spell differed from how Alzur’s Thunder was portrayed in the source material. Tissaia’s spell was more devastating and potent than the books, where Alzur’s Thunder wasn’t meant to wipe out entire armies. Nevertheless, this spell was always strong enough to kill its target with a single strike.

The toll on Tissaia was too great

One of the things that we noticed in ‘The Witcher’ is that magic takes a toll on the mage’s body. Unlike Ciri, who could use magic without relying on chaos, mages have to use chaos to cast magic. As such, the more powerful the spell is, the greater the toll of chaos is. 

At the end of season 1, Yennefer used a powerful flame spell that killed the Nilfgaardians on Sodden Hill at the cost of her connection with chaos. That was why Yennefer couldn’t use magic throughout the events of season 2.

So, in that regard, the toll of Alzur’s Thunder on Tissaia’s body was so great that we could see how it hurt Tissaia while she was casting it. Her hair was turning white as she was thundering down on her opponents. And after casting the spell, she was visibly weakened by its effects.

In the last episode of season 3, Tissaia decided to commit suicide. She explained in her suicide note that the cost of chaos was much too high for her that she believed that only her death could pay the price for casting Alzur’s Thunder.

This explains why Ciri called this spell a spell of last resort, as it has a heavy toll on the caster’s body. And that’s why no one attempted to use the spell before Tissaia decided to put her life on the line to keep her companions and home safe from their enemies.