Resounding no on this...Listen to what you did. You capture as many resources as you could, turtled till you had ridic amount of mana, then used one of the most powerful spells in the game. How about suggesting they make the AI take steps to keep you from getting to that point? Even a suggestion to maybe add to the potential skills/abilities of units/heros a 'mage-dodge' that is on top of the resist (note, this should be a rare high level trait, equal to the cost and rarity of the spells)...
I hate 'nerf' mentality. Don't take something that makes people feel like, gasp, they are actually as powerful as the lore says they are through magic (keeping in mind the time and resources allocated to achieving it). How about, equally as powerful counters? .....
When I say I captured everything I could, that wasn't a good thing. There were very few resources I could get. I was Empire side, so I couldn't place a second city anywhere I had access to due to no fertile ground. I had two directions I could go, both cut off by the opponent. I made settlers just to make an outpost to capture a single resource three times. So I had one level three city, out of food, out of gold. Cruel was often the tax rate just to keep up with the level three city and meager army I had. It wasn't like I captured a ton of resources.
I didn't do anything because I didn't want to declare war on an enemy supposedly much tougher than I was by trying to cross his boundaries. So I sat and did nothing. And was rewarded for it by an overpowered spell. If there isn't a cooldown on it, there should definitely be a cap. Or... actually have the enemy use ultra-powerful spells against us. The worst spell in three games used against me so far was "Chaos". I would prefer that to be honest... but then I can hear people complaining when the 250 point spell kills their sovereign first every fight, with nothing you can do about it.
If you make it a three turn cast, yes, you can do insane damage... but the enemy at least has a chance to kill you first, or disrupt you. And you won't be able to spam it like I did. Even when facing nine enemies, I just walked backwards, then cast. Almost nothing ever got close. It's an overpowered spell, and I did nothing to earn it other than click "end turn".
So... yes, I say nerf it. Either with multiple-turn casting, or a damage cap... (100 or so feels right).
And Cloud Walk... ok... you don't like a 20 turn cooldown... then make it cost 400 mana. This is an ability that lets you auto-defend anywhere you want just by keeping one killer group together. We need to get away from the mentality of one group game-winners.
And of course, I'd love the AI to be better. But I know that's being worked on. If I can Cloud Walk/Mana Blast/Growth/Giant Form my way to victories, I pray so can the computer so I'm actually nervous about fights. Otherwise, this game won't have any replayability. Right now it's just a matter of picking which unbeatable path you want to take to win as opposed to worrying about winning.
Telaeus