The next upgrade is back in the Phendrana Drifts so return there. If you're thinking there has been a lot of commuting lately then don't worry; there are many more new locations to be explored now.
Before going on, it's a good idea to save at the Save Station nearby.
Scale the ledges toward the door leading to Ice Ruins Access just like the first time you were here, but stop on the ledge above the entrance to the Save Station. Turn around and you will see a hovering platform you can reach with a double jump. From there look out across the valley to see another hovering platform a bit below and some distance away over the water. It looks too far to reach even with a double jump but it's possible. If you're having trouble then get a running start and hold off on the second jump until you're nearly level with the platform you're going to. From there it's an easy hop to a ledge with an ancient looking portico and the only exit you haven't passed through yet.
Blast the wall of ice here and time your way past the Bombus to the other end of the passage.
Chozo Ice Temple
There is a Baby Sheegoth at ground level here. Defeat it and then start scaling the ledges up the walls. There are Crystallites and a new creatures, Ice Parasites, patrolling some of these ledges so clear them if you think they will get in the way. The Ice Parasites are cold adapted versions of the Parasites you saw on the frigate. Try to get a scan of one because they will be gone the next time you're back here.
When you reach the top, jump to the ledge to enter the temple proper. There is a frozen fountain here but you don't have a way of melting it at the moment so you need to find the way out. Scan the grate on the right to learn that it is adorned with the image of a Chozo Shaman. You may remember passing four similar statues in the hall leading to the fountain. Go back and scan them to find they had various jobs: butcher, baker, candlestick-maker, and Shaman. Scan the Shaman to reveal that it's made of brinstone which is susceptible to missile fire. Fire a missile at it and the statue breaks revealing a Morph Ball slot. Activate the slot and the grate opens, so go through the door behind it.
This is a Morph Ball maze and you need to solve a bit of a puzzle to get through. Two bombs will break the metal boxes so you can get between levels, and one bomb will destroy the stone sections of cylinders. The rest will be easy enough to figure out.
Chapel of the Elders
You enter a large square room and on the other side you can see your prize, the Wave Beam. As you approach, it recesses into the floor and walls drop in the corners revealing Baby Sheegoths.
When you've finished off the Sheegoth, your Wave Beam rises back out of the floor, so pick it up. The Wave Beam opens purple doors as well as the blue doors which will open with any beam. You'll need the new weapon to escape the room.
As a weapon the Wave Beam is most useful against mechanical enemies. It can also be used against Bombus, so you can take them out now instead of dodging them. In general the Wave Beam has more power than the Power Beam but it's rate of fire is a bit lower. The Charge Beam in combination with the Wave Beam is useful to paralyze enemies for a few seconds.
Chozo Ice Temple
When you get back to the Ice Temple you'll find that all the creatures there before have been replaced by Bombus, which is useful to practice your new ability to defeat them, but bad news if you missed your chance to scan the Ice Parasites.
There are now two Baby Sheegoths here; this is a hub for Phendrana so they can be annoying after a while. It's probably a good idea to save now since the Save Station is handy.
Expansions (Phendrana Drifts)
There is only one new place which can be explored now, but it will take quite a while so we'll only get a start now and the rest will be covered in the next two pages.
Ice Ruins West
Return to Ice Ruins West; note that you don't need to go through Ice Ruins East this time because you can double jump up to the door leading to the Ruins Entryway via one of the floating platforms.
You'll probably want to clear the Baby Sheegoths so they don't bother you while you're exploring. Go into the building on the right as you enter. Jump up the ledge with the Chozo inscription, then Jump across to a higher ledge, and right to a third ledge. Enter a short passage on the right to see a stalactite of ice hanging in front of you. Get a scan of it to learn that a missile will dislodge it and turn it into a handy platform. So fire a missile, watch as the stalactite crashes to the ground, and drop down in front of it.
Since you probably got turned around in the building you might want to take a moment to figure out where you are in relation to the entrance. You'll be using the stalactite several more times and it will be handy to know where to find it.
Now jump onto it and jump again to the wall behind it. Go through the stone arch on the extreme left to a rooftop. There are Ice Shriekbats in an alcove in the distance, so scan them if you did't get them before, then shoot before they attack. Cross the roof and jump to the ledge under the Shriekbats' roost, then jump to the right to a ledge with a purple door behind it. Use the Wave Beam to open it.
There are two swarms of Scarabs and a Bombu in this passage.
This is a flooded courtyard with platforms of ice scattered around. There is a very tall platform in the center, apparently Space Pirate technology.
Go to the ledge on the left and notice a new device just the right size for a Morph Ball to roll into. Scan it to learn that it's called a Spinner and it's Boost Ball powered, so roll in and use the Boost Ball a few times to activate it. Now go to the other end of the courtyard and do the same with the Spinner there. Each time covers open on large spigots above courtyard.
When the second Spinner has been activated a Morph Ball slot is switched on. It's on a ledge and you have to scale some of the ice platforms to reach it. Activate it and water comes flooding out of the spigots, raising the water level in the courtyard. Several floating ice platforms rise with it, so hop across them to a ledge attached to the central platform. There is one more floating platform beyond, so hop to it and then to a small ledge with a tunnel opening. The ledge is under a bit of an overhang so make the last hop a double jump and wait until you've dropped a bit before the second jump. The water level will lower after a bit so you have do to all this before the timer runs out; if you don't make it in time the start again at the Morph Ball slot.
When you've made it to the ledge, switch so Morph Ball and jump into the tunnel; you land in a small room where an Energy Tank is waiting. Drop into a hole here to come out at the bottom of the courtyard.
Get back to the Morph Ball slot and activate it again to raise the water a second time. Hop the floating platforms as before but this time stop at the ledge attached to the central platform. Hop to the ledge on the right and then to a stone ledge nearby. Scale the stone ledges and make a final double jump to the top of the central platform.
There are three exits at this level: one has no power so you can't go through at the moment, one has a purple door but ignore it for the moment, and the third has a door with a blast shield. Fire a missile to clear the shield and go in.
Save Station A
It's not clear why the first Save Station was B and this one is A, but as long as you can save you should probably do it. It will be a while before the next one.