Why does one opponent give so little XP? (in General)

As I was steaming through my favourites list, I noticed one chatacter gave me tiny XP rewards compared to the others.

'Night' (65,126 MPR, 64,376 Score, 46% Challenge Bonus) was giving me around 150XP a win.

That's a drastic reduction compared to the characters just above and below him.

'Phire-Phrog' (79,415 MPR, 67,349 Score, 53% Challenge Bonus) around 660
'Hall of Fame' (44,582 MPR, 61,309 Score, 39% Challenge Bonus) around 570

Why does a character with a larger Score and MPR give about the 5th XP per win as a guy below him?

MPR is also taken into account for rewards somehow?

How would the MPR matter? 'Hall of Fame' has 21k less MPR than 'Night' and gives nearly 4 times the XP anyway.

Were the stats updated?

But the far smaller MPR charcater (Hall of Fame) is giving 5 times the XP the larger (Nights) charcater is? :/

I could update them mate, but Nights is still giving out tiny XP.

And he's still between both Phire and Hall.

Updated stats. I inspected each in turn before fighting.

Phire-Phrog
Score: 67,349
Power: 71,338
MPR: 79,415

XP: 639 (Challenge Bonus 48%)

Night
Score: 64,367
Power: 67,213
MPR: 65,126

XP: 244 (Challenge Bonus 42%)

Hall of Fame
Score: 61,309
Power: 65,508
MPR: 44,582

XP: 661 (Challenge Bonus 35%)

Why does Night consistently give such low XP?

Some more fight rewards, including cash this time;

Phire
Cash: 184
XP: 625

Night
Cash: 47
XP: 159

Hall
Cash: 175
XP: 538

Okay, well. I don't get it.

I got on Worth the Risk and fought all three. Got identical rewards, basically. So it must be something unique to you.

The ONLY thing that is different between Night and the rest, really, is the creation date (Night is old as heck) and the rounds it takes you to beat him (ALWAYS 7, far less than anyone else)

Not sure how either of those things would matter though.

The only thing that makes sense to me is that the MPR listed on the page is actually the VPR and Night just hasn't trained in forever. Which is what I'm guessing is the case.

VPR can only be higher than MPR though, in which case, if Night had a load of untrained XP, and a massive VPR, I should be getting higher rewards shouldn't I?

with that score? I think the opposite. When a character has a higher MPR and a low score, I think you should be getting less.

What about Phire-Phrog then? He has a much higher MPR, with a lower score, yet still gives much more rewards.