Interesting quirk in the ECL/LA - XP system

[Quasqueton]

I made a fire giant NPC for my campaign. With 15 HD, and +4 LA, he is a level 19 character (although only a CR 10). As soon as he earns one level (fighter in the case of my NPC), he becomes a 20th-level character and he no longer gets xp for defeating other fire giants (CR 10s).

Heck, even without adding a single level, fire giants (CR 10, ECL 19) get no xp for defeating frost giants (CR 9, ECL 18). And hill giants (CR 7, ECL 16) are a waste of time for both.

Interesting. I'm not complaining or ranting or anything. I just thought this a funny quirk in the LA/ECL system. I mean, even a 6th-level fighter gets xp for killing stock orc grunts by the half-dozen a round.

Quasqueton

 

[Li Shenron]

Nice catch

 

[Darkness]

Vrock: 10 HD, LA +8, CR 9.

No xp for other vrocks.

 

[Pinotage]

But doesn't a ECL 19 creature get the gear of an ECL 19 NPC? In which case I'd expect it to wipe the floor with most CR 10 creatures. Gear counts for a lot, particularly at those levels.

Pinotage