After getting all of the Gems and Relic, on top of all of the Crystals you should already have, the game makes you fight Cortex again, as will be the only button you can use in the Warp Room.
True to its title as a Remaster, this fight is still the same as it was before. The only difference is what Uka Uka says at the start and what happens to him and Cortex at the end. So beat them one more time to see the new ending.
Because N. Tropy is now kaput, there was no one left to tend to the Time Twister Machine. It finally went berserk and imploded on itself, with Uka Uka and Cortex being the first victims of an all-consuming portal of doom.
Thankfully, Crash, Coco, and Aku Aku were able to escape from the Time Twister machine in time. They came back home to see Polar, and they also brought some new animal buddies. Crash managed to bring back a Baby T-Rex, while Coco was able to bring back Pura.
Aku Aku has no clue what happened to his twin brother and the rest of the bandicoots' enemies, but he's sure that they won't be seeing them for a very long time.
As it turns out, Cortex and N. Tropy were taken into a violent volcanic site with no hope of surviving it for long, especially since the destructive time portal also turned them into babies! All they did from there was play Tug of War, with Uka Uka being the unfortunate thing they were tugging on.
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No credits or Developer Time Records this time, you're instantly sent back to the Warp Room as if nothing ever happened to it.
If you got only Gold and/or Platinum Relics in every single level of the game, go to spot of the Load/Save screen in the Warp Room where Coco used stand by in the PS1 version, and one extra Gem will appear. Grab the Gem and enjoy the fireworks!
(Awww man, come to think of it, though video would've been great to time two days ago...)
Unlike the PS1, the fireworks will last for as long as you stay in the Warp Room, instead of lasting for a few seconds. It's a pretty nice improvement, but you're still gonna miss them afterwards.
You can actually get this Gem before facing Cortex, but I held off on it until after I defeated him again to make that Gem offer more closure to this playthrough.
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At this point the Crash 3 part of N-Sane Trilogy is done. Or at least the raw version of it. There's still a lot more to do in this whole Remaster, and I'm not just talking about Fake Crash...
This game has new DLC levels, plus, Crash 1 and Crash 2 have Time Trials just like Crash 3 already does. The Time Trials in those games are simply just for bragging rights and aren't required to complete this version of those games, but I wanna take 'em on and see how many Platinums I get out of them, too.
So while all 3 of my main playthroughs are done, now it's finally about time to tackle on new things that have never seen the light on the original Playstation.
Stay tuned for more Crash Mania!
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See how I closed out of the original PS1 version of this game, here!:
• Crash Bandicoot 3: War...