The strategy I use is one I haven't used since "Bone Yard".
First, I hunt down the challenge Gem. Like Crash 2's 25th level, it utilizes all 5 colored gems to get through the Gem. This time it's in this order: Blue, Green, Purple, Yellow, & Red.
The Green & Red Gem platforms, in particular, even take you to paths that match their own colors. After the Red Gem, you reach the 2nd Clear Gem of that level.
Then, since I didn't hit any Check Points, I intentionally kill myself yet again to go back to the very start of the level, where I now go through its Time Trial.
The trio tower of Aku Aku crates are still present during this Time Trial, so you have a guaranteed, flawless opportunity to initiate the invincibility from them.
I'll settle for a Gold Relic for now, but I'm sure I was only a few seconds away from a Platinum.
Now at this point, I've beaten this game 99%, and since I should have more than 25 Relics at this point thanks to Levels 31 & 32, Level 30 is the last level I need to take care of.
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See my N-Sane Trilogy run through this level's Multicolored Gem Path AND Platinum Relic, here!:
• Crash Bandicoot 3 (N-S...