Sin had an intense desire to progress further in this place, wherever 'there' may be. He was determined to push forward despite any obstacles or challenges. Even utilizing his wood clone, he was able to successfully pass the 42nd floor with relative ease.
Based on this accomplishment, Sin believed that his wood clone could likely advance even further without much difficulty - perhaps even beyond the 50th floor. If his cloned wooden form was able to handle the obstacles and enemies of the 42nd floor, then it stood to reason that it could continue dealing with subsequent threats and tests up to floor 50 and potentially beyond.
Extrapolating from this, Sin theorized that his true, original body could potentially reach floors greater than 60. Since the wood clone was an extension of himself, albeit weaker, he conjectured that his real self would be capable of pushing past 60 floors and deeper into this structured progression of levels.
This estimation took into account the increasing danger and difficulty inherent in advancing further. Past the 60th floor, the standard enemies and monsters would be level 60 or greater. Additionally, each floor held boss enemies whose levels began at 91 on floor 60. The boss of floor 70 was known to already be at level 100.
So while the challenges grew greater with each floor cleared, Sin had confidence that his capacities in his natural state would be up to the task, especially if his wood clone could make it to floor 50 or higher. This incremental increase in threat level was noted, but did not deter Sin from believing he could move meaningfully beyond floor 60 with his true self.
The strength evidence from his wood clone's feats suggested his real body held enough power and skill to handle enemies tens of levels higher. How much higher would depend on unknown factors going forward, but he estimated a minimum of 10 floors based on the current pace of difficulty.
Of course, there was a limit to how far any being could proceed in this realm of escalating adversity. But Sin felt assured, for the time being, that his real form was ready and able to press on past the 60-floor milestone, perhaps even reaching the 70s or 80s if his wood clone could surpass floor 50 without issue.
He simply needed to rely on his own abilities when the time came to break through to the next major threshold. The challenges of floors 60 and beyond would be demanding but achievable for Sin's true self, fueled by confidence from his wood clone's earlier successes.
There was no definitive outcome guaranteed, as greater dangers lay ahead. But Sin believed in his capacities enough to boldly progress further, striving to reach as far as he possibly could. Equipped with his skills and emboldened by his duplicate's feats, he was motivated and poised to advance deeper through cunning, power, and indomitable will.
The path forward would only get harder, but Sin felt resolute in his belief that his real body could handle it, to push meaningfully further into the 60+ floors. How far exactly? That remained to be seen. But he was ready and driven to move beyond the 60-floor mark and confront all the intensifying threats that awaited him.
Here is a 500+ word rephrasing and expansion of the sentences without a concluding paragraph:
After parting ways with Eric and Gerald, Sin proceeded directly into the dungeon using Kamui. He started on the 42nd floor, as this was the deepest level he had reached so far on his own. The magical structure of the dungeon imposed a firm rule - an adventurer could not progress beyond a floor they had previously visited unless accompanied by a team.
Sin harbored a desire to skip ahead and enter directly at Floor 50 or beyond. However, some intrinsic property of the dungeon itself prevented this, denying him access to those deeper levels. He did not yet grasp the underlying reasons behind this restrictive system.
Despite not fully comprehending the nature of the limitation, Sin found himself bound by the dungeon's regulations. While able to teleport directly to Floor 42 with Kamui, the enchantments woven into the dungeon's foundations barred him from going any further alone.
It was perplexing to Sin that this magic could discriminate based on his prior progress. The dungeon somehow tracked which floors he had reached previously and prohibited transporting past that point.
But the complex, arcane forces maintaining the dungeon's stability were well beyond Sin's current understanding. Their origins and purposes were opaque to him. All he could do was accept the reality that solo access was confined by his deepest successful venture.
However futile, Sin felt the urge to rebel against this mystifying constraint. He harbored ambitions of pushing much farther, well into floors beyond the 50th. Yet the abstruse energies regulating the dungeon stymied such attempts.
It was conceivable there were hidden reasons for this regulation that might make sense if properly understood. Perhaps it related to difficulty scaling or fairness toward other adventurers. But ignorant of the true rationale, Sin felt thwarted and tangled in forces beyond his comprehension.
Still determined, Sin considered workarounds that might trick the dungeon and bypass this vexing limitation. Could he disguise himself to appear as a team rather than an individual? Would teleporting to the next floor down right as a party member left work? But he suspected the ancient enchantments perpetuating the dungeon's integrity would see through such ruses.
Without a full grasp of the intricacies of the dungeon's inner workings, Sin was unable to circumvent or overcome the block on accessing floors solo beyond his known progress. The magic was simply too arcane and impenetrable to him currently.
And so, resigned to accept the opaque but rigid limitations placed on him for now, Sin began his solo descent on Floor 42. The rationale behind the dungeon's deeper mysteries eluded him still. But he would continue working within its established bounds to penetrate deeper, seeking answers and greater mastery of this realm.
Though the dungeon's logic was confounding, it also strengthened his resolve. Sin would fully unravel its secrets in time and gain unrestricted access to its full depths. But first, he needed to thoroughly plumb its upper levels, moving steadily lower with or without companions until finally the deepest reaches laid open before him, unobstructed and understood at last.