How is magic affected in critical mode?

[Hoarse_Phuqer]

I just started replaying the game in crit and am really enjoying it, but it seems magic has been massively nerfed

It sucks because I really enjoyed having a magic build for Sora the first time around. Admittedly I'm only halfway through Toy Box at the moment, but does your MP meter grow at all later on? Is an MP build still viable in critical?

Also, with all the features we got on the critical mode update, did this affect the proud mode as well, making it a bit tougher this time around?

 

[okhi12]

The critical MP meter grows a bit after some progression, but as Sora's HP, it finally reachs only half the length it has on proud. Both physical and magic damage are nerfed. You can still use a viable MP build through the cooking minigame, eating meals that temporarily increase magic and the MP meter. Some keyblades and transformations are better suited for magic, that with the use of accesories that enhance magic or increase the number of spells you can cast before the MP runs out and enters the MP charge will help a lot. And of course the indisposable MP haste(ga). At the beginning of the game magic is very limited when playing on critical, but once you progress you'll have access to enough resources to get a more than decent magic build. It's just more difficult, but that's what critical is for... to learn how to use wisely all things the game has at your disposal. Relying much on magic at the beginning is nearly impossible, but it'll become easier over time. As grand magic situation commands tend to appear less frequently, I would't expect for thundaja to save the day too often.
About changes on proud after the update I don't know, I only played proud the first time, when the game came out. I don't think they changed anything because nothing was announced about that.