Teclis is too frail and sickly that he could not properly ride a griffon.

There were times Teclis wished he had learned to properly master a griffon, but he never had. It was a skill that only the strongest of elves could learn, and it was an art that had to be learned young. In his youth he had been too sickly. He would never be able to ride one of these magnificent creatures into battle without first paralysing its fierce will with magic, which would defeat the whole point. He would need to use a spell of stupefaction to make the thing docile enough to ride."

Giantslayer (Warhammer: Gotrek & Felix) pg 18.


"Teclis muttered an apology and limped forward, dragging himself wearily into the saddle and
buckling himself in. Not for him the bravado of some young elves who rode bareback and
unharnessed, and performed tricks on the backs of their steeds. He made sure all the buckles were in place, feeling slightly embarrassed as he did so. This was the way a child would ride, but he was taking no chances of falling from the saddle.

Giantslayer (Warhammer: Gotrek & Felix) also pg 18.


"He wove a spell of levitation, feeling resistance to his spell as he did so. The corrupting
influence of Chaos was interfering with his pure elven sorcery here. Even as he cast it he could see the beastmen come closer. He was not afraid… yet. He had overcome greater odds in the past. The spell took effect and he strode upward. The ceiling here was perhaps ten times the height of a man above him, and each step took him closer to it. If the beastmen chose to lob missiles at him there might be some problems, but he knew spells that would ward him against that. He was not too worried about any spells the Chaos warrior might possess. He had complete confidence in his own ability to deal with such things. He had long ago learned that there were few magicians in this world
that he need fear."

Giantslayer (Warhammer: Gotrek & Felix) pg 36.


"Teclis followed them and so did Gotrek with barely a shrug and a sniff. Knowing that the others
were waiting for him, Felix put his feet in the water and the answer to the mystery became clear.
Just below the surface was a narrow causeway, cunningly concealed so that it could only be seen from close at hand. The men of Crannog Mere obviously knew the way by heart for they did not need to look down. Nor did Gotrek, who always seemed sure-footed in these situations. Close inspection revealed that the elf really was floating just slightly above the surface of the water, effortlessly and doubtless by the use of magic."

Giantslayer (Warhammer: Gotrek & Felix) pg 71.


"Teclis hurled himself upwards, invoking the spell of levitation. He strode into the sky at the end of his leap, hoping that it would confuse his foes and get him clear of their blades. There were grunts of dismay from below as the greenskins realised that their prey had eluded them. As he had intended, the mist had covered his movements."

Giantslayer (Warhammer: Gotrek & Felix) pg 125.


"Teclis invoked the spell of levitation and marched upwards into the air, determined to put himself above the melee. At the same time he invoked multiple overlapping shields, reinforcing those created by his charms and amulets. A brilliant golden sphere surrounded him. The din of battle decreased as the warding spells blocked it out. Even so, the giant’s screech of pain was almost deafening, as was the thunderous crash at it fell to the ground. What was going on, he wondered, unwilling to take his eyes off the Chaos mages? Surely the Slayer could not have killed the giant? It was a feat that beggared belief."

Giantslayer (Warhammer: Gotrek & Felix) pg 146.


He invented a levitation spell based on riding pegasus.

"He cast his mind back to his first flight on Silver Wing’s back, when he
had tried to derive a spell of levitation from first principles. It was time to
put that spell to the test. He summoned more power to him, and stepped
upwards as if walking on an invisible stair.
One step at a time, he walked upwards into the sky above the battlefield
and saw all of the carnage laid out beneath him. He saw the thin lines of the
asur being overwhelmed. He saw Tyrion rally the high elves again and
again, his blade a burning banner, the dragon armour of Aenarion terrible to
his foes. He knew that given the weight of numbers, eventually even his
twin would be pulled down."

The Tyrion and Teclis Omnibus (Warhammer Chronicles)

Silver Wing is a pegasus that he is forced to ride to rescue Alarielle and Tyrion. It died only a day of riding and guess why. He is a terrible rider. He also has to be buckled on like a child so he could not fall!

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