Ninja Gaiden 3 Walkthrough Part 14 – Day 6, Part 1 – Howard Phillips Plains, Antarctica
Start moving straight forward through the base toward the crates in front of you. From there break left and start into the path between the snow drifts. You will be ambushed by Assassins (and worse) as you press forward through the drifts. Focus on the most enemies first then worry about the others when all else are dead.
After Ryu slides down the slope, move forward as best you can. Keep alert and the moment you hear Cliff talk about enemies start going for the bow. Any time Ryu gets a clear view of soldiers on snow mobiles, blast them. The mobile soldiers may have back up so keep moving and attacking at anything with some form of pulse. Cliff will mention that the fight has been happening on a crevasse when it is nearing its end
After the fight an avalanche occurs. Start moving immediately to jump and stab some kunai into the wall. Climb up the wall, evading the falling chucks of ice. It just takes one to kill Ryu here so be careful. After you dodge the falling piece and get close to the top of the second, then it will start to slide. Evade over to the next chunk and scale to the top. Once there, you will find a Falcon waiting for Ryu. Save and move on.
Head deeper into the Ice Cave. Just after Cliff radios about your objective, 2 Megaslions and 2 Ourboros attack Ryu. Take out these as the ice floor begins to shatter under the weight of the battle on it. Once it begins to slip, focus to find a climbable wall. Dash toward it to start up it immediately.
At the top Ryu needs to press forward. Turn right and slide underneath the wall through the small opening. Slash or slide your way through the lightshell bugs that are blocking your way forward. Follow them back to their nest and destroy it with an arrow. Bird Flip up the walls into the next area.
At the top you have more Lightshell bug and Homunculi, if not fiends. There may be one Megalion initially. Defeat them all then move over to the back left-hand side of the room. Focus to spot a Lightshell bug nest above you. Target it with an arrow. When you blast it, Megalions and Ourboros will come at you. Defeat all them (or their stronger counterparts) then make for the back left wall again. This time you will want to Wall Run and Jump onto the ice drift that is on the wall in front of Ryu. Climb up it to move on forward.
Once at the top Ryu wants to go down the slope. From there he needs to wall run across the gap. When you land, follow the prompts and jump when needed to survive the descent. At the bottom Ryu will encounter his first fiends of the game (on Normal). Be sure to go for overkill on these guys as they have a tendency to get up and explode otherwise.
Once the fiends are dead, climb up the wall behind them. AT the top press forward. Defend all the fiends at the top. These things are very easy to counter attack so use that. After the initial round, a second fiend, A Magna Persona Fiend, will appear. Now start moving and do not stop. All the fiends Ryu killed earlier will rise and a number will explode! Dodge out toward the wall you climbed up and wait out the explosions. Once they stop start focusing on the fiends and the Persona. With the Persona, when you see its forehead glow, shoot it quickly. After a few shots it transforms into a second fiend, simply Magna Fiend. These love their scythes and should be avoided if Ryu is swarmed with other enemies. If you manage to get either the Ultimate or the Ninpo ready, then use it to quickly end the battle.
Once it is over Ryu should head for the doors. Push them open and you get a quick cinematic from elsewhere. Press just a little forward to find a Falcon to save at.