Incinerating Fire was a Fourth-level spell that had a hundred percent compatibility with Merlin's previous spells. As for Fiery Collapse, it was a powerful Pandora Demon Ability.

Merlin now had a slight understanding of Pandora Demon Abilities. This mysterious and formidable power did not have to be specifically under certain spells but compatibility!

This kind of compatibility was virtually the same as the compatibility between spells. There was also compatibility between Pandora Demon Abilities and spells.

For example, it was absolutely impossible for Glacial Finger to be compatible with Fire-type spells. They were basically two different Elements and two different powers.

However, Glacial Finger could be compatible with Ice-type spells. Certain Ice-type spells had extremely high compatibility with Glacial Finger.

Therefore, with high compatibility, the Pandora Demon Ability could be successfully cultivated.

Merlin had now constructed a brand-new Fourth-level spell. Its prominent characteristic was that it conformed to Merlin's own characteristics as well as the characteristics of the spells he constructed in the past. As long as he successfully cultivated Pandora Demon Abilities for the previous spells, then there was no problem cultivating a Pandora Demon Ability for a Fourth-level spell with a hundred percent compatibility.

That included the merging of Fiery Collapse. Under the suppression of the Flame Maxim as well as the long amount of time it fused with Fire-type spells, the fusion between Fiery Collapse and Incinerating Fire was quite smooth.

"Phew…"

After a long moment, Merlin breathed out a sigh of relief. He held out his hand gently, and a flame emitting white light rose from his hand. It was Incinerating Fire!

"The fusion was a success. Incinerating Fire and Fiery Collapse merged, and its power was instantly raised to a level that's comparable to a regular Seventh-level spell. However, this is merely the first form of Fiery Collapse!"

Just by relying on Incinerating Fire, the strength was comparable to a Sixth-level spell, much less by adding Fiery Collapse. The power instantly increased to the point of a Seventh-level spell.

Furthermore, it was just the first form of Fiery Collapse. There were still second and third forms of Fiery Collapse. Now that Merlin had constructed a Fourth-level spell, he could cultivate the second form of Fiery Collapse.

Merlin still required the treasure from the ancient monument to cultivate the second form of Fiery Collapse which was pale white. After all, the treasures needed to cultivate the second form of Fiery Collapse were quite special.

"The third form of Darkness Eye can kill a regular Seventh-level Spell Caster! If Fiery Collapse is cultivated to its second form as well, its power would be terrifying. It might even be able to kill a regular Seventh-level Spell Caster."

Merlin carefully thought in his heart that between Darkness Eye and Fiery Collapse, there was no comparison between the two types of Pandora Demon Abilities.

The power of Fiery Collapse might not be as powerful as Darkness Eye. However, if it was fused into a spell and coupled with the strength of the spell itself, its power would be quite considerable.

Moreover, the new Fourth-level spell was derived by Merlin. From then on, Merlin would no longer be a traditional Spell Caster. In the future, the Fifth-, Sixth-, and even Seventh-level and above Spell Casters would have no practical reference significance to Merlin.

That was because Merlin had already embarked on another path — a way to derive spells and understand the essence of Elements alone. It was a path to becoming a Great Legend!

In the Spell Casters' most glorious era, the number of Spell Casters who started deriving from Fourth-level spells were quite rare. However, those Spell Casters were terrifying. Generally, Spell Casters who started deriving from Fourth-level spells did not simply aim to be Great Wizards, but the position above the Great Wizard – a Great Legend!

Only Great Legends could condense a Maxim and explore the essence and true meaning of spells. Deriving spells by oneself was the beginning of exploring the essence and true meaning of spells. They were better than Spell Casters who started deriving spells from the Seventh-level onward.

The probability of becoming a Legendary Wizard after starting to derive from Fourth-level spells was quite high.

Even Merlin himself could vaguely feel that the spells from ordinary Wizard were no longer suitable for him. After all, the Spell Casters who just merely constructed spells were simply too weak. In the Spell Casters' most glorious era, ordinary Wizard used a combination of spells and Pandora Demon Abilities which could burst into incomparable power. That was the true strength of Wizards.

Unfortunately, the number of Spell Casters were rare now. All sorts of inheritances had been submerged in the long river of history. One of the most common Pandora Demon Abilities could make many Spell Casters go crazy. It simply could not be compared to the Spell Casters' most glorious era.

Even in the Spell Casters' most glorious era, only Merlin was a Wizard who was extremely valiant and had unlimited potential!

The fusion of Incinerating Fire and Fiery Collapse was successful but that did not mean the end. On the contrary, it was just the beginning. His Mind Power was enough to support him in constructing several new Fourth-level spells!

"I'll need to consume some power of the Maxim to derive the spells. Although the power of the Maxim is extremely valuable, it's not my own power. Only by deriving spells and constructing them in the Awareness would I be able to control this unique power! Next, I'll derive a Fourth-level Darkness-type spell!"

Merlin took a deep breath. This time, he wanted to derive a Fourth-level Darkness-type spell.

Currently, Merlin had Zero-level spell Dark Mist, First-level Dark Light Realm, Second-level Darkness Tide, and Third-level Darkness Vortex.

These were all Hallucinating spells. If Merlin wanted to derive a new Darkness-type Spell, he should move in that direction if he wanted it to obtain a hundred percent compatibility.

Originally, Merlin already obtained a Fourth-level Darkness-type spell Darkness Nightmare in Abyss Fort. He even had Fifth- and Sixth-level Darkness-type spells. They were all extremely complicated and powerful spells.

Among them was a Fourth-level spell called Darkness Nightmare, which seemed to have reached the pinnacle of illusions. Thus, the Fifth-level and above Darkness-type spells began to develop in the direction of illusions and reality interfering with matter.

Merlin also considered ahead of time that the Fourth-level Darkness-type spell he wanted to derive should also be developed in this direction. Not only were Hallucinating spells strong but it could also influence a Seventh-level Spell Caster's Mind Power.

Even if a Seventh-level Spell Caster could not be dragged into an illusion, he still had to be affected. Besides influencing, it also had to possess strong offensive power.

This was the Fourth-level Darkness-type spell that Merlin needed!

"Matrix, start the analysis. Derive all Fourth-level Darkness-type spells!"

"Beep, commence derivation!"

Deriving an entirely new spell required a large amount of time. Especially this time, deriving a Darkness-type spell seemed to be even more complicated, so the time required was even longer.

Merlin simply waited quietly.

After waiting for more than ten hours, the sky outside the Wizard Tower gradually darkened, and the Matrix finally finished deriving a new Darkness spell.

"Beep, a total of three hundred and forty-three Fourth-level Darkness-type Spell Models have been derived!"

The Matrix had derived more than three hundred Darkness-type spells. Merlin did not look at them immediately, but instead rushed to check on the Flame Maxim in his Awareness.

The change in the Flame Maxim was obvious. Merlin could clearly feel that it seemed to have become smaller. Deriving Darkness-type spells really did consume the Flame Maxim a little.

Currently, Merlin only had one Maxim. Therefore, this sole Flame Maxim was especially crucial. Every little loss could not be recovered.

"Only two more Fourth-level skill can be derived. Otherwise, I'm afraid the Flame Maxim will really be exhausted!"

Merlin secretly decided in his heart that after Darkness-type spells, he would only derive two other Fourth-level spells and no more. The Flame Maxim could be used but it could not be completely exhausted.

He would leave a little to better suppress Darkness Eye as well as Fiery Collapse, just in case of any accidents.

After looking at the Flame Maxim, Merlin focused his attention on the Fourth-level spells derived by the Matrix. These three hundred or so Fourth-level spells mostly had high compatibility, and there were several dozen with a hundred percent compatibility.

However, Merlin only selected a few spells that had a hundred percent compatibility. All these spells had powerful hallucination effects, and none was inferior to Darkness Nightmare.

In the end, Merlin chose a spell that could not only influence the mind of a Spell Caster but could also stimulate a slight strangling power, which could strangle a Spell Caster trapped in an illusion.

For this spell, Merlin named it Darkness Illusory Death!

Now that a brand-new spell was derived, the next step was to simulate it in his Awareness. Merlin had done this step countless times, so he was already very familiar with it.

Soon, he simulated Spell Model of Darkness Illusory Death in his Awareness and merged it with Darkness Heart. It also smoothly raised to the second stage as well.

For Darkness Heart, as long as a Fourth-level Darkness spell was constructed, it could reach the second stage directly. It was also the strongest form of Darkness Heart and could improve the strength of a spell by five to ten times.

This was quite frightening. Merlin's Darkness spells were already powerful to begin with. Their destructive power could not be compared to Fire-type spells, but when it came to the degree of bizarreness and the effects of dealing with Spell Casters, Darkness spells were definitely the most powerful.

However, once a Spell Caster had reached the Seventh-level, his Mind Power would evolve, and the advantages of Darkness-type spells would be less obvious. As they were simply pure illusions, the advantages would turn into disadvantages as well.

However, Darkness Illusory Death was not purely an illusion as it also had the power of strangulation. Coupled with the amplification from Darkness Heart, it could also easily kill a regular Seventh-level Spell Caster!

"The two most important spells have been derived. The next choice would be much easier."

A smile appeared on Merlin's face. He had decided the next spell he would derive to be a Wind-type spell.