This is the final part of a 5 part series.
Links to the first 4:
Part 1: Large and in charge [solved]
Part 2: Small and resilient [solved]
Part 3: Immovable object [solved]
Part 4: Unstoppable force [solved]
(parts 1-4 can be solved out of order)
Now for Part 5:
A good problem solver peers into the past,
once you find me, it's quiet at last.
Completing this riddle is the ultimate test,
for after its done, you will need your rest.
The other day I screamed "JSTYX" out loud all confused,
To figure out what it means, I'd be greatly amused.
As a great riddler, I've not spoken this word,
for if I had, that'd just be absurd.
After some twisting and thrashing, I'll have solved this problem,
the four other parts, I'm sure that I've solved them.
The problems the key, I know it, I know it,
But instead of sharing I might as well throw it.
As with the past, a similar method involved,
This time it's much harder, and has greatly evolved.
With all of these pieces, you look back in time,
This is the end of the puzzle, but not my last rhyme.
What/who am I?