DISCLAIMER This is 100% NOT ACCURATE. This is an interpretation of many Time Attack vods and the recollection of a handful of people I consulted on this issue.
I thought I would take a few hours to interpret data and present figures that would closely represent the experience that most of us remember from the Official servers.
There are 2 major points that I think would best replicate the Official charge system.
Let's assume the Nanoblast meter consists of 10,000 points that you have to accrue to get your SUV or Beast Mode. The following figures will be based on that total amount.
1: Damage Given
There seems to be 4 tiers of mobs that give a set amount of of Nanoblast Charge based on the damage that any given player deals to them
Low tier mob: 5% (or 500 points)
High tier mob: 10% (or 1000 points)
Rappys and Jaggos: 15% (or 1500 points)
Bosses: 35% (or 3500 points)
Assuming you take 0 damage, killing 1 low tier mob will give you 500 points if you deal 100% of the mobs health by yourself. There is also a diminishing return based on level, being overleveled decreases nano income by 10% for every 10 levels over, capping at 50%. So if youre over leveled for the mission by 50 levels, you accumulate nanoblast at a rate of 50%
2: Damage Taken
1% of HP in damage taken equals to 20 points (so 50% would give you 1000 points)
I've struggled with this value. I'm having a hard time showing it with actual math, but I'm pretty sure this is actually lower than it was on Official. I think its safer to undershoot it than to overshoot it, though.
Damage over time from status effects and Protranser traps seem to work identically with these numbers as well.
These figures average Nanoblast Charge Rate from 90 to 150 seconds depending on the mission and party quantity. We can have the discussion on if that is too high or too low, but that's how it was to my recollection on Xbox Official. It also falls in line with the vods of solo and party play that I've been watching for the last few hours.
PLEASE challenge me on these numbers. I'd like to have discussion based on past experience and the community's vision for what Clementine should be.
Footnote: Shoutout to Wolfe in Discord for bringing up the 10k total figure earlier today, I'm not sure if that's actually how it worked on Official but I think it helps quantify the Charge Meter with a point based system.
Shoutout to Milandruil and Victorix XVII for all of their Time Attack vods from all those years ago. It was a great source of data that allowed me to compare runs against each other with different weapon and class types.
Shoutout to Milandruil, Mr. 305, and SeedExpress for looking over this data with me and punching holes in the various theories I tested out.