Items Collected:
Elves Obtained: 6: File:MMZ Nurse Elf Icon.PNG Cyber-Elf Charnue, File:MMZ Nurse Elf Icon.PNG Cyber-Elf Miloppe, File:MMZ Hacker Elf Icon.PNG Cyber-Elf Clocsule, File:MMZ Animal Elf Icon.PNG Cyber-Elf Birflow, File:MMZ Hacker Elf Icon.PNG Cyber-Elf Itemass, File:MMZ Animal Elf Icon.PNG Cyber-Elf Beehitt; EX Skill: File:MMZ2 Kougenjin Icon.PNG Kougenjin (A or S-Rank only)
Crystal Cave is the crash site of the bombardment aircraft, within walking distance of the Resistance Base, a place where special E-Crystals were mined in the past. The giant hunk of steel and rocket fuel weathered an ill-fated landing, but it didn't go very far. Now, it's toast. What is now Neo Arcadia's trash is Elpizo's treasure. It's a gold mine of spare parts, except he's looking for just one. Ciel sent out a search party, but they've been gone long enough to make her think something's up.
Amongst ship debris, Zero gets transferred to the soldier's meeting point. Something has gone wrong: no one has reported in. Ciel is plauged with a bad feeling as the mission begins.
Rough Territory
Crystal Cave is a little ways off yet. That gap is filled with enemies prepared to ambush Zero. Carryarm-Spiking pairs don't hesitate to barge in while you rush up the first slope. Then, when you get to the top and make your way down, prepare for tricky ones to pull attacks from behind.
At the bottom of the slope are spikes. Dash-jump and keep moving.
Pantheon Guardians are in your way, but they are hardly a challenge.
Optical Illusion
(Beware: This isn't recommended during the mission!)
The path will fork into a chasm below, where a Carryarm can attempt to toss a Spiking in that will rebound a few times before the constant impact short-circuits it and it explodes. The chasm obviously ends with spikes below, and just has E-Crystals, so it would see that falling in is plain crazy. However, this is just the first of many mind tricks in this confusing place. Hug the edge of the right wall as you drop down, and you'll hopefully land in a hidden passage off to the right. Keep trying if you mess up; it's a doozy getting down here. The passage hides a Z-Panel, and Cyber-Elf Box that holds File:MMZ Nurse Elf Icon.PNG Cyber-Elf Charnue, the other Elf that gives you 2 extra lives when full-grown.
After a quick leap up to higher ground, you'll be sneak-attacked again nearing the downhill slope. It pays to stay alert in this level: soon, it will be a case of one wrong step, and you're a goner.
A Perplexing Climb
You can go into the cave entrance below, or sidetrack off to the upper path above with a quick wall-jump. Skip the upper path if you're attempting the mission; it takes too long to accomplish this side task.
Up here is a Top Gabyoall. Don't get caught off guard, as enemies will pull sneak attack stunts again and again throughout the level. When you reach a dead end, wall-jump up. A Cyber-Elf Box is hidden up a staggered cliffside. It requires perfect precision to get up the increasing steeper cliff edges, but it's impossible to get all the way to the Elf, so what do you do? Simply strike the Cyber-Elf Box with the Z-Saber through the rock, and it will bust it open. Let the Elf come to you, and you'll get File:MMZ Nurse Elf Icon.PNG Cyber-Elf Miloppe.
The Crystal Caves
Down below the Cyber-Elf awaits Crystal Cave. The cave will test your patience and memory skills, and even has a special secret.
Just past two Pantheon Guardians is a very sketchy dropoff. Spikes are everywhere in sight. You need to be extremely careful now: you must shift back and forth across walls at the right time, or get skewered. Any mishap will be fatal. Hug the left side of the wall as you drop to avoid the first set. Then, after you pass them, immediately move over to the right side, just below these spikes, to avoid the second set. After geting past these, move back to the left wall below them to stay away from the third set of spikes.
Don't be too much of a daredevil. A Pantheon Guardian, thoughtlessly placed trapped above spikes, is waiting to send you to your doom. Try to gun him down before proceeding. Keep to the left wall, and keep jumping back up if need be, just not high up near the spikes.
Enticing Danger
(Beware: This isn't recommended during the mission!)
The following drop in the chain of danger uncovers a terrifying challenge- reaching a Cyber-Elf Box on a very, very narrow ledge, above- you guessed it- spikes. If you want it, keep to the left wall and hold 
for dear life. This way, you'll make contact with the side of the ledge and narrowly miss doom. You can then claim File:MMZ Hacker Elf Icon.PNG Cyber-Elf Clocsule, which cuts charge time in half for one mission. Getting out requires a very hazardous dash-jump, which is why this elf should not be a priority.
If you're skipping the Elf, shift to the right again instead of staying to left, right after getting past the set of spikes on that side. After the spikes below the Elf, you're safe- for the moment. Hold 
and drop down all the way.
Glittering Crystals
After getting past a entrance that seems more like a tooth-filled mouth than a way in, you'll be able to explore Crystal Cave. There's a solitary Pantheon Guardian just before an E-Crystal at the edge of an abandoned mine shaft. After you get past the Pantheon, prepare to take on a spike-filled underworld....
Just when you'd think you're at wit's end with this level, a suprise enemy pops in. This firefly-like Mechaniloid is a Hottalook. It will follow you, so there's no use in outrunning it- you can get hurt by touching its intense glowing spotlight.
Unlike other enemies, you can't destroy the Hottalook, but you do need to attack it. Hottalook is actually a special guide robot sent into the mines to light up the otherwise clear crystals covering spikes below. It changes color according to the color of the platform below it, red or blue. At first, E-Crystals sitting in mid-air will give away platforms, but later on, you'll need to check to see if there is or isn't safe ground below, provided you don't have the area memorized. Fire away at Hottalook with the Buster once. Hottalook will light up the way and show you the crystals that cover the ground, but respond to the unfriendly fire and release three Mini-Hottalooks. These will fan out in a progressively bigger circle and guard Hottalook. However, you can destroy these. Destroying a total of 10 will get you File:MMZ Animal Elf Icon.PNG Cyber-Elf Birflow.
The first area of crystals has sets of exposed spikes near the end of the mine shaft. The difficulty level isn't wicked just yet. When you reach the other side, watch out for an incoming Top Gabyoall. Beyond it is a steep drop down into a second mine shaft.
If you'd like to find another Cyber-Elf after the mission, fall all the way to the left of the screen to land on a small ledge and get a health pick-up, then dash jump a little to the right and stay in the middle of the screen to land on another ledge. If you move too far to the right, spikes will get you. Drop off the side of this ledge and hold along the jagged cliff face, even after falling off. If done right, you'll land right by a hidden shutter door.
Optional Sub Boss: Golem Type E
Of all places, Golem Type E makes one final appearance in this already haphazard area. There's no need for much effort beyond a couple of charged Ice-attacks from the Z-Saber. Neo Arcadia likes to guard its treasure quite intently, and beyond the Golem is a set of three E-Crystals, and a Cyber-Elf Box concealing File:MMZ Hacker Elf Icon.PNG Cyber-Elf Itemass.
More Crystals... More Danger
Ignoring the Cyber-Elf and dropping all the way down brings you to the second area of Crystal Cave, and a huge increase in difficulty. There's no free rides from here on out. While the first set of crystals had no enemies beyond Hottalook, Pantheon Hoppers lurk everywhere in the second cave, especially in your way, but this time, cutting 3 down to size results in a Cyber-Elf; File:MMZ Animal Elf Icon.PNG Cyber-Elf Beehitt. It will come to you if it's above spikes.
Another Hottalook will drop in to say hello. Without E-Crystals exposing platforms, rely on it again. You will need it. Some Pantheon Hoppers can also be useful. They may stand on hidden platforms, and their loss is your gain if they land on spikes. When they get destroyed, the spikes are obviously exposed.
After some simplistic jumps, next come not-so-easy ones. The gaps between spikes and safe platforms will increase, and the crystal platforms shrink in size. Eventually, you'll discover crystal on the walls as well as the ground with Hottalook's light. These are the final strike of difficulty for the Crystal Cave. The first section that does this has a small gap where you can slip through after wall-sliding down the upper crystal. Dash-jump over to the narrow platform ahead, then again for the next.
Last, but not least, comes an even more perplexing set of crystals blocking the exit. Dash-jump up to the crystal above, and again, slide down into the gap onto the crystal below. Dash-jump one last time to safety, and give yourself a pat on the back- you've weathered Crystal Cave. Now, it's time to get out. There's no spikes your way anymore. Instead, Pantheon Guardians and E-Crystals are in sight, a nice end to a hard area... or so it looks.
Brainwashed Soldiers
Right after you exit the cave, you'll reach the Bombardment Aircraft (the exit point after completing the mission). Zero will discover the missing Resistance soldiers, but each is under the influence of a mind-control antenna. Ciel warns Zero not to harm them.
You need to climb up the ladder of the aircraft, but with Resistance soldiers shooting at you, that can be a problem. Even worse, they're you're own men, so you can't kill them: that's just evil, and you'll lose 2 points for each of the 10 who die. Instead, if you must, shoot them only once with the Buster to stun them for a few seconds and get by. The E-Crystals are just there to tempt you, but there's a full health refill behind one soldier. You will definitely need full Sub Tanks and health for Harpuia.
The roof on the ship has the ever-annoying Signaloids to deal with. Between them are more soldiers, making charging attacks a hassle. Stay sharp and keep moving forward.
The final section of the ship has a few soldiers you might need to shoot to get past, but again, only shoot once. When you get to the ladder that goes into the ship, don't climb down. There's nothing in the ship to find at the moment. Beyond the ladder is the nose of the ship. Appearing for the final time in the game, and for that matter, series, a Carryarm will drop a Spiking down to roll after you. Just dash down quickly, and it won't catch up. A futile attack from a now defunct enemy.
Finally, you'll drop off the edge of the ship to find two sets of E-Crystals. Get them. You won't get another chance to explore the area that contains them.
You've probably noticed a fierce thunderstorm has built up outside. It's just a sign of what awaits. Dash a little further down the wasteland to see.
Zero will discover Elpizo with the Baby Elves, but not in time to keep him from getting what he needs. Elpizo chuckles and expresses his content at getting closer to his master plans as he transfers out.
Unfortunately, Zero arrives just after Elpizo leaves- and just in time to bump into Sage Harpuia, leader of Neo Arcadia. He, too, was late upon arrival. Harpuia notices Elpizo has snatched the IFF beacon, short for IDENTIFICATION - FRIEND OR FOE. Harpuia ponders the reason for taking that particular device, and for breaking into Neo Arcadia's facilities on his own. He sums it up as the behavior of an inferior of the Resistance, and turns his attention on Zero and confidently tells him he's going to die. After pulling out his swords once more, he's ready to attack!
Boss: Sage Harpuia
If there's one thing Harpuia hates, it's defeat. He has grown FAR more skilled than he was in his last fight with Zero. You can't get him stuck in the same attack over and over this time. Harpuia has his old skillset, but he's packing a lot more speed, and can do perhaps the most damage out of any boss in the game with his new EX Skill alone. He is still weak to Ice atttacks, but much harder to hit than before. His health bar has dropped to two bars like Leviathan, but again, he's not kidding around for his rematch: he really could kill you. Because his attacks demand speed, equip either the Rise or Active Form if you've got either unlocked.
Harpuia usually starts the fight by jumping into the air like before, but his sonic slices are unleashed much faster than usual as he flies left and right. Again, speed is key against a supersonic warrior with a jetpack.
When Harpuia gets the chance, he can try to dive in mid-air, tackle Zero, and perform a skull-smashing takedown. Not fun, because like before, if you get caught, you're stuck for the unpleasant ride back down. Keep out of his clutches by dashing away.
If ignored, Harpuia will launch his seeker missles from his swords, but even these are smarter than before. They now charge in faster and have electrified tips. Slash them and destroy them. One on screen is bad enough, but a swarm is fiendish.
If struck by any attack, including an Ice-element strike, Harpuia gets knocked to the ground, but he will not be trapped in a pattern of sonic slices anymore. Instead, you'll probably get the equivalent of a slap in the face- a hyperspeed dash, followed by a sweeping sword slash, then an uppercut. Harpuia can even knock you for a loop if you take a hit from his own dash. Dash-jump right before he gets to you and leap over him.
Harpuia can still launch his triple-hit sonic slices nontheless, and more precise. He'll make two slices, then a sonic boom slash that launches an X-shaped wave at you. Don't get up in Harpuia's face unless you're prepared to hurt- a lot. Stick to the other side of the battlefield and try to hit Harpuia with the Buster.
Harpuia also has the advantage of a high-range targeting attack. If left flying long enough, Harpuia raises both swords, charges the X on his chest with energy, and sends an electron blast into the sky that draws lighting from the thunderstorm above, and this skill is enough to penetrate Zero's insulated metal armor, and he's simply one big lightining rod. Dash back and forth , because if you stay put, you'll be zapped multiple times. If you think this is bad, wait until Harpuia's health gets low.
EX Skill: Supersonic Rain
At A-Rank and up, Harpuia taps into the most frightening EX Skill of the game: Supersonic Rain. He'll launch into Overdrive with a green burst of flames, becoming invincible, and violently sweep back and forth, delivering VERY horrendous and humongous sonic waves down to Zero. It takes incredible speed and timing to dodge the lengthy onslaught, and you will suffer if you fail to dodge. Each time you take a hit, you lose a huge chunk of health! Obviously, you can be careless, but you'll also be creamed.