That was how Leon found himself three years later. Inari had popped in, declaring him sufficiently prepared for his second tail, and informed him of a new creature he had introduced to the environment, specifically to help catalyze his evolution.
Thus far his energy diet consisted primarily of magical creatures and monsters once he had graduated beyond more mundane animals.
While he had slain his fair share of higher energy bearing individuals, he required a vastly more powerful foe, at least compared to his level, to provide the explosive potential needed to push him to the next level.
Inari had only gone so far as to tell him of the creature's existence in the area. The hunt, study, and destruction of his enemy would be left entirely up to Leon.
This would be a true life and death struggle, one where he would either succeed and evolve, or die. Leon fully planned to succeed.
He had a Devil Lord to conquer and a Seraph to taint, no magically inclined pest would stop his ascent to power.
Inari popped out of existence and Leon immediately began scenting the air.
It was a few short minutes later of lurking in the deepest shadows of the trees when he finally detected a whiff of the new arrival and immediately regretted it. The stench was foul, even at his current distance.
With a crinkled nose, Leon set off in pursuit. The sooner he killed the monstrosity tainting his little kingdom, the better.
He didn't have to wait long. Lumbering through the trees in apparent confusion was a true monster.
A forest troll.
From various mythologies and fantastical sources, Leon dredged up what he could remember about the disgusting creature before him as he lurked in the shadows.
Of note, trolls were incredibly stupid, which was apparent by the bumbling of the brute as it passed before him.
In some tales, trolls had incredible regenerative vitality. Crippled by fire, those usually weren't the muscle head type like the one before him, being built strong yet more compact.
Leon was inclined to believe this held a closer resemblance to the trolls of the Harry Potter universe.
Big, dumb, but with immense strength, if the massive club, which was essentially a tree, was any indication.
He couldn't fight this kind of enemy head on, at least not as he currently was. While it remained standing, he could not land a fatal strike.
A single blow from a monster like this would spell his end.
There were alternative solutions; if he could shred its Achilles tendon or hamstring the monster, and it would fall, giving him access to its vulnerable throat, but it would be safest to exercise patience.
If it knew it was under attack, it would thrash and fight in its death throes. This would be a hunt in every sense of the word. He would stay in the shadows, waiting for a moment of weakness.
Even magical creatures eventually had to rest.
Not fighting it head on would decrease the amount of energy he received upon its death, but with how much magical potential it held it would be negligible for his current needs.
The rest of his week followed a very similar routine. He would only leave his quarry every few hours to eat, drink, and take very brief naps.
Even on a hunt, the hunter had to keep its strength up, and the troll was a difficult prey.
The troll's inherently magical nature kept it moving far longer than would be possible for normal creatures. Its path was littered with partially consumed corpses of various types of beasts; fuel for its unhindered trundle through the area.
A full week of constant travel had left Leon in a foul mood. He was grumpy with lack of sleep, and his fur was matted and tangled in places, having forgone his regular baths to maintain vigilance over his prey.
The pair had been climbing the nearby slope of a mountain for some time, still surrounded by trees though they had thinned slightly.
It was hunting for a den, a cave still resided within its natural habitat.
The lower slopes of this mountain were littered with caves, so it was only a matter of time until the most dangerous part of Leon's weeklong vigil was upon him.
While it's true the troll would sleep and provide an opening to strike, the enclosed space of a cave would be immensely limiting for speed and movement.
If he was too slow, or worse, missed the jugular in his strike, or even both, it was likely he would die.
If he missed, but survived, it would become a hunt of attrition. The troll would know it was being hunted, and free strikes would no longer be possible.
Leon would have to revert to his human side's ancestral style of persistence hunting, harrying his prey until it fell from exhaustion or blood loss if he was feeling brave enough to give it death by a thousand cuts.
The troll finally stumbled across an appropriately sized den during Leon's contemplation.
He would wait, to give it time to sort out its new home and allow it to fall into a deeper sleep. He had been patient this long; he could continue for another span of time.
An hour crouched at the mouth of the cave, peering around the corner through the gloom as his quarry circled the cavern before finally laying down. An additional hour, to ensure its sleep was deep and undisturbed. It was finally time.
Years of practice made him less than a ghost. A deadly specter, floating along on silent paws.
Twenty steps.
Fifteen.
Eight.
Four.
One.
He stood directly before the head of his prey, massive yet delicate throat exposed to the air as deep heaving breathes resounded within the cavern.
His current size would only guarantee half of the throat to be shredded sufficiently to cause death.