Now that would be fun…
I was thinking, though, someone uses an alternate universe Olmak to go into the Red Star, and use the Olmak as the teleporter. Also, there would be a chance, very small, that someone might be able to find most of the pieces of Brutaka’s mask, and repair it, hotwiring some parts, to create a relatively stable mask. It might not have the integrity to withstand jumping around constantly, but it could create, say, a two-way portal between the Red Star and Bara Magna, allowing for its evacuation onto the planet.
Or, as a last resort to kill Marendar, The Order causes the Red Star to crash into the surface of Bara Magna, like in @Lees_L 's Bionicle Rise Intro video. The crash kills Marendar, but causes an influx of beings who shouldn’t normally exist in this dimension, such as the Kestora and the spectral mask from the Silver City Pocket Dimension.
Yeah I also thought of killing this team in Bionicle rise. but I haven’t thought about how to kill Marendar yet, but the Federation of Fear is a good opinion.
What is makuta powers? Thanks
EDITED FOR DOUBLE POST - Spiderus Prime
When Tahu used the Golden Armor to destroy the Rahkshi army in Journey’s End, he gained the powers of all the Rahkshi he destroyed (each Rahkshi, of course, having one of the 42 “Makuta Powers” listed here: Kraata Powers - BIONICLEsector01).
Greg has stated that he would not have allowed Tahu to possess all 42 powers, though it has been specified that he at least has Heat Vision and Quick Healing, and it is likely (though not explicitly confirmed) that he gained at least a handful of other powers. After all, there were “plenty” of other Rahkshi types present:
wow. so that’s golden armors function?
More like a side effect.
The primary function of the armour was to destroy all Antidermis within reach, in the event that the Makuta went rogue. Kind of like how Marendar was designed to destroy all Toa.
I can’t tell you why the Great Beings thought it would be a good idea to destroy a group of potentially-dangerous beings worthy of a safeguard by giving their potentially-dangerous powers to another potentially-dangerous being that they already deemed worthy of a separate safeguard.
i personally wouldn’t have marendar killed by anyone, I would actually treat him kind of like the geth from mass effect, where he starts simply following his programing to kill toa, but then over time he starts displaying traits that don’t make sense with his programming. like am I the only one who can imagine a shot of marendar with his arm out and having a butterfly-like Rahi sitting at the end of his finger just having him look at it with confusion. my reasoning for thinking this is it really seemed like bionicle was going to explore the ideas around ai wether that is what we wanted or not, personally marendar could of been used very well to show this idea of a machine (not literally, he’s probobally more like a creature that is brainwashed by programming to kill) going against it’s programming
I imagine the same thing with Marendar sitting on a rock, thinking to itself: “Is this a pigeon?” “Life, huh?”
I like that AI arc idea
neat, that sounds cool.
I just want to say that reading the posts here is a blast, and it just goes to show how adding a hypothetical and a little community interaction can really elevate a topic and bring people together. Just something I saw, and thought should be commended. 
Oh my goodness, this is beautiful. So beautiful, in fact, that I think it’d be a perfect fit for the GHIDONICLE Fanon Contest #2! This moc is amazing, but the entry period ends soon, so I’d recommend you enter soon if you’re interested.
I appreciate the thought and the love for the design! 
I’ll have to decline tho
I don’t think this MOC belongs in a contest; it’s already had its time in the spotlight, so I’d love more to see other interpretations join said contest and shine
Thanks tho!
EDIT: It also doesn’t qualify for the Ghidonicle Contest anyway due to scaling, and we don’t have Chick-Fil-As here in the Philippines for me to use the prize on if ever 
Creepy. It looks like a Makuta. Very sturdy looking build though.
Kopaka had big death flags in The Powers that Be, Marendar would for sure take him out. Or, maybe Pohatu dies, encouraging Kopaka to stay in the Toa
business.
Helryx sacrificing herself to it would also be poetic, given her usual pragmatism. Orde dying too would be a solid blow.
I don’t see Takanuva or Tahu biting it though, they’re both just too important to the story. Unless Marendar is the end all be all, I imagine they stay a while longer.
My vote goes to any of the above mentioned, as well as Lesovikk. The poor guy’s been through enough, let the man rest in peace. Plus, he can use that to prove he didn’t kill Karzahni.
As for who kills him, my vote is to feed the guy to the automated defenses. The Baterra see its weapons and charge it. Nuparu sicks a legion of Boxors on it. Set up some turrets. You could even reawaken the Bohrok swarms, they’re not doing anything else. The thing is a heartless machine, so let the heartless machines take care of it. Maybe a Toa deals the finishing blow, but the key lies in lowering his defenses.
That’s a great looking moc.
That’s terrifying. They could legitimately kill Marendar with sheer numbers.
With all this evidence in the Headcanons topic for Kopaka having ridiculous mental strength, it got me thinking:
We know that Lewa was able to overcome a krana through sheer force of will. If Kopaka is truly as mentally strong as has been theorized, could he wear a krana Xa and control the Bohrok swarms, or perhaps even the entire hive mind?
I’d imagine it would look pretty awesome to have a krana-wearing Kopaka leading the entirety of the Bohrok swarm into battle against Marendar.
(I’ve already covered earlier in this topic why I don’t think Marendar should be killed, but this could at least make for a pretty sweet temporary victory)
Without a doubt.
Source: BIONICLE Chronicles #2: Beware the Bohrok
“Help!” Lewa cried. “Someone, over here! Quickly — please!”
Kopaka rushed to his side. Lewa was dimly aware that the Ice Toa was dressed in Exo-Toa armor of his own.
“Drive it back to the cavern,” Kopaka said tersely. “We can’t fight it here.”
Lewa breathed out in relief. Miraculously, Kopaka’s cool, no-nonsense voice had sent the voices away. Nearby, Gahdok roared in fury.
Kopaka casually told the Bahrag Queens no through somebody else’s mind just by talking.
The idea that he could override the swarms simply by being hooked into the system is extremely feasible IMO; the only concern I’d have is whether or not he could mentally hold commanding the entire Bohrok swarms all on his own with no breaks. Cadohk and Gadohk were essentially designed to do nothing except exert mental control 24/7, and that kind of ordeal may be too much for Kopaka, but it would definitely make for cool writing - Kopaka having to take breaks due to the magnitude of the strain.
Marendar facing the Bohrok Swarms would be an interesting fight - I would much rather see a Miserix/Artahka fight against Marendar than a Tuyet fight, as a Tuyet fight would go one of two ways, and both anticlimactic.
I could see him handling it; the entire crux of this theory is that he has beyond-Makuta-level willpower.
That being said, the burst-like nature of his control could make for dramatic storytelling.
As I said above a while back, I’d want to see Marendar fight Tuyet, though not necessarily 1v1; the other ideas you have are also great, and I’m sure there are plenty other Marendar vs. ??? matchups that people want to see.
As per the original purpose of this topic, I’m just going to lay out my entire version of Marendar’s post-canon story, and how it involves Tuyet.
Marendar doesn’t come out as a main threat right away; it mostly stays in the background, picking off the occasional Toa as the other main story threads build up (The Yesterday Quest, Velika’s Plan, the other Great Beings, etc.). Eventually, though, Marendar becomes too big of a threat to ignore, and the story shifts to Marendar as a main villain. This is where the story could go nuts on the big showdowns, with multiple groups and individuals trying to take down Marendar to varying degrees of failure.
During this time, Marendar kills Helryx. In addition to all the reasons that people have given above for Helryx’s death, I also have a Tuyet-specific reason for killing Helryx that I’ll explain later below.
Eventually, this culminates in a final showdown where a group of Toa trap Marendar in a Toa Seal. I’m thinking this would be the Yesterday Quest crew plus Tahu, Tuyet, and Lesovikk, though I’m not super committed to any of those six besides Tuyet (it’s important that Tuyet plays a big role in this battle).
However, this is where my interpretation of Marendar becomes important: I see Marendar as basically being a “Toa 2.0” with Elemental control over crystal. Not only is crystal shown to be resistant to Elemental powers in the Matoran Universe, it’s also one of the few substances that no Toa can control, making it perfect for a Toa hunter.
With its control over Crystal, Marendar is able to unexpectedly escape from the Toa Seal and attempts to kill one of the Toa, only for one of the others to sacrifice themselves and step in front of the attack. I’m thinking Lesovikk sacrifices himself for Tahu, but, again, I’m not super committed to the exact characters; the important thing is that Marendar sees that Toa are willing to act selflessly and starts to question its duty.
With its duty in question, Marendar flees the battle to reconsider things. Eventually, the Toa/New Society send someone to negotiate with Marendar. My first choice for this role is Gali, given her leadership position in the New Society and her history as the peacekeeper of the Toa Nuva. Gali is eventually able to convince Marendar of the worthiness of the Toa, and gives up her Toa Power to become a Turaga as something of a peace offering.
However, despite the truce with Gali, Marendar can’t exactly become a main-character hero, as too many characters wouldn’t like that: Toa who don’t trust it; Agori who want to see it complete its mission; Great Beings with their own secretive plans; and who knows what else. During this time, Marendar mostly stays out of the way, with the occasional contribution to whatever story threads are going on at the time. However, I think this could also be a great opportunity to flesh out Marendar as a character, perhaps forming meaningful alliances and friendships with a choice few beings (maybe even some Toa; I know Kopaka planned to become a solo adventurer if he ever gets back from the Red Star, and I’m sure Pohatu would tag along. It could be interesting to see Marendar join up with them).
However, at the same time, Tuyet is using the recognition she got from contributing to Marendar’s “defeat” to build her Toa Empire, creating an army of Toa from loyal Matoran with the immense amount of Toa Power she’s stolen from other dimensions. Building a loyal following would also require silencing anyone who knows about her past actions, which is why I had Marendar kill Helryx earlier: Helryx has to be dead for the Toa Empire plot thread to move forward, but I’d rather she die to Marendar than Tuyet; it’s fitting that the First Toa should die at the hands of the first “New Toa”. Also, frankly, Helryx is hard to kill; I think it’s more realistic that Marendar could kill her than Tuyet.
(I think Tuyet would also go after the seven Turaga of Metru Nui/Mata Nui, but that’s not really relevant to Marendar)
Eventually, Tuyet’s Empire makes a big move on Spherus Magna, and this is where Marendar comes back into the story: the truce with the Toa was based on the fact that the Toa meant no harm, but Tuyet just proved that wrong. At this point, Marendar goes back to killing Toa, and it makes sense why: the Toa Empire is legitimately a textbook case of exactly what Marendar was meant to prevent. First, though, Marendar would also go after the Toa that it sees as the leader behind an orchestrated betrayal from all Toa: Gali.
And, being a Turaga, I honestly can’t see Gali surviving a targeted attack from a vengeful Marendar. With Gali dead, Marendar goes back to being a primary villain for multiple factions, going after Toa even more aggressively than before: now it’s motivated by personal vengeance on top of its programming.
And it wouldn’t just be Toa anyone; Marendar would be killing anyone assisting the Toa Empire, which, in Marendars eyes (eye?), just means “anyone helping Toa”; Matoran, Turaga, even Glatorian and Agori. At this point, Marendar’s characterization is absolutely critical: due to it’s feelings of betrayal combined with Ignika-like naivety (due to its relative youth), it’s gone beyond just killing problematic Toa, or even Toa in general, and is now killing those that it was made to protect. Done right, Marendar is a sympathetic, tragic character, with many parallels to Tuyet, the one who started this whole thing.
Now, despite everything I’ve written above, I have no idea how to conclude Marendar’s story. I legitimately can’t think of any character worthy of ending Marendar’s rampage beyond Marendar itself, or perhaps the close friends that Marendar made before Tuyet’s Empire went public. If Kopaka’s struck out away from the New Society on his own (with Pohatu), I could see him being willing to kill in this circumstance. Heck, he was pretty close multiple times in the canon story. Maybe this is where Kopaka’s ridiculous mental strength could take center stage.
Depending on how the other story threads play out, there might even be a way to kill Marendar that hasn’t even been introduced in the story yet.
I suppose a Crystal Nova Blast would take Marendar out of the story, as well as many other characters; I don’t think anyone is breaking through a miles-wide field of Toa Seal-quality crystal. Timed right with the many other plot threads going on, this could be a major event throughout the entire story. At the very least, taking out Tuyet would be a good ending for Marendar, finally fulfilling its duty to protect Spherus Magna from Toa run amok.
Of course, there are also countless other “big guns” that could reasonably take down Marendar. The Golden Skinned Being is still out there, as is the Vahi, and I’m sure that some of the Great Beings could cook something up if they wanted to.
Very interesting ideas you have there