With Splash Woman's Laser Trident weapon uploaded, Mega Man reached the end of the tunnel and found his way to the fortress itself. It proved to be almost classic Wily in design, complete with the skull in front...which immediately told Mega Man that this was some sort of frame up. Wily would never use one of Vinyl's projects in a world takeover attempt without her, and Vinyl would never let the fortress be without her neon horseshoe symbol if she were a major player. Of course, knowing it was a frame up didn't tell Mega Man who was actually behind it...and beyond that, he still needed to shut it all down.
First, of course, he actually needed to make it into the Fortress, and the approach had several deep pits separating the platforms he had to leap across, with sentry spheres popping up out of the pits to shoot at him, while bird bots dropped rocks towards him. Once again, Mega Man did his best to avoid destroying the bots trying to shoot him, so they could continue to work once the situation was fixed.
Once he began climbing the outside of the fortress towards an entrance, he found large propeller platforms that could only be activated with the Tornado Blow weapon, which caused a great deal of wind to blow upward. While this did drain a good amount of weapon energy, he was able to find energy cores along the path to restore it.
Once past the platforms, he encountered new bots that looked like Guts Man on tank treads, only much smaller and carrying a shield. A few shots caused them to drop the shields so they could be damaged, and Mega Man was unfortunately forced to destroy them, as they were blocking paths completely.
As Mega Man climbed, he noticed the weather turning stormy, with lightning flashing amongst the clouds. He began to worry about what was happening with the incomplete weather systems of the planet without Tornado Man guiding them. He just hoped that Gravity Man had found a way to adjust, and it wasn't straining him too much. He continued to worry about this even as he battled another copy of the dragon bot he'd faced in the Geothermal center Magma Man had controlled.
Once past the dragon, Mega Man had to time jumps past lava being launched from one tube to another directly above him, using Rush to spring him up when he had a clear path. Other familiar obstacles littered the path in new combinations, but Mega Man already knew how to deal with each, and was able to continue climbing upward with ease, now inside the building itself.
Finally reaching a guardian chamber, Mega Man found four face-shaped turrets guarded by spike balls that slowly made their way towards him, which he could push back with buster shots. As he shot, the turrets also shot the spike balls, trying to push them towards him. If the spike ball reached the turret, they would explode and be replaced by another as the spike ball returned to the center of the passage. If the spike ball reached Mega Man's end of the tunnel, it would return to the middle and the turret would start firing shots that phased through the walls, locked onto Mega Man. This would end when the turret was destroyed.
After destroying enough turrets, new ones stopped coming, and eventually Mega Man managed to destroy the last turret. He paused then, taking a few breaths to prepare himself mentally for the next challenge. "Whoever designed this place has been studying my tactics," he murmured softly. "I'm going to have to be careful..."
The next segment of the fortress proved to be far more roundabout, twisting and turning up and down as Mega Man made his way deeper inside. Thankfully, there were several opportunities to use his abilities to take various shortcuts past the more complicated segments, allowing him to conserve his strength for deeper in.
The major obstacle that Mega Man encountered as he continued were projector enemies that would fly into the room and generate holographic platforms that were indistinguishable from those Mega Man needed to jump across, save he would pass right through them. Thankfully, Mega Man countered this by taking a literal mental snapshot of platform positions before the projectors did their work.
After dealing with another flower mini-guardian on a clock set of platforms, Mega Man dropped into an underwater sector, dealing once more with octopus-in-pot robots. At this point, Mega Man decided he was free to blast his way through, as this fortress certainly wasn't part of Vinyl's plans for the planet.
Several solid blocks filled various paths through the water, but Mega Man discovered they could be destroyed with a single shot of Laser Trident...making it, in his mind, one of the more useful sub weapons this trip, as it could also be fired the most before it ran out of power. It allowed him to make his way past most other obstacles as he made his way back out of the water.
Once out of the water, he had time to dry off before he reached the next Fortress Guardian. The Guardian itself, right at first, looked like the tail of a giant mechanical fish, which fired trios of homing missiles at him out of a hatch near the 'tail fluke'. The hatch itself proved to be the only vulnerable point, which exploded after he managed to land enough shots.
The Guardian then moved more towards him as he rushed forward, revealing what looked like a floating sub design in blue and yellow. It hovered above Mega Man, had a spiked bottom, and two hatches that dropped fish-shaped bots onto the ground to either side of him to charge at him as the vehicle moved up and down. Mega Man managed to deal with it by timing his jumps to shoot the hatches without impacting the spiked bottom...though he messed up a couple of times. Thankfully, the spikes only caused damage rather than frying his circuits as most of these spike traps would if he made contact with them.
With the hatches destroyed, Mega Man made his way to the front of the vehicle, which had what looked like the head of a snub-nosed swordfish, perhaps. Here, the vehicle moved up and down, its mouth opening to fire a charged laser blast at him. Despite the blue white coloring, one accidental contact showed Mega Man that it was in fact a laser blast rather than a sonic disruption blast, as it only drained his shield energy rather than punching a hole straight through him. Thankfully, this end was easy to damage, as Magma Bazooka could be charged to launch a much bigger blast of flames, which tore through the vehicle's shields readily.
As the vehicle finally went down, Mega Man leaned back for another few deep breaths. "Okay...it's not the Wilys doing this...but whoever is isn't too bad at this either..." He made a mental note to look into who, if anyone, had the potential to pull this off once he was back on Earth.