Ratchet & Clank 2: Locked and Loaded

I heard this game is one of the most difficult ones. For me the most difficult challenge in this game was The Impossible Challenge - but only because I wanted to do that on my first visit of the Joba arena.

I have PAL version of this game and apparently it's one of the versions that do not have subtitles. Also the Mapper does not show crystal locations here.

I played through the game 3 times.

I bought everything I can. Upgraded every single weapon in the game to it's most advanced version. Most weapons have 3 upgrade stages, some do not have any and some have just 1 upgrade stage. I even upgraded the Clank Zapper (took me nearly half an hour on Grelbin).

Basically I bought and did everything I could in this game.

1st playthrough
Collected 39/40 platinum bolts (I forgot the 1st one)
Earned 27/30 skill points (you need to play through the game again to earn the rest)
Did every mission, upgraded almost every weapon to their advanced form.
Found all the desert crystals & moonstones.
I bought second to most advanced armor in the game. I didn't buy any before that as I think it's just a waste of bolts.

2nd playthrough
Collected the last platinum bolt near the end of this playthrough.
Earned 1 skill point for maxing out nanotech.
In this playthrough I mainly just grind bolts to buy MEGA version of weapons and also I focus on upgrading as many of them as I can to their ULTRA version.
In NG+ there are some new challenges in arenas - I show them all.
As my main focus are bolts I do everything that can get me some - so all the races, arena challenges, everything once again.
Here I bought the most advanced armor in the game.

3rd playthrough
Here I mainly focus on upgrading the rest of my weapons.
As soon as I don't need more bolts I stop doing optional challenges/races.
I think this is where I buy RYNO and most of the most expensive weapons in the game (I bought the rest of them in my previous playthrough).