I was doing that with Cesar with like -25 wait total, gave Himiko the item that gives brave every turn, using Palamedes to steal brave and Michelangelo to zero out enemy brave. However that final fight against britannia is horrid since nearly everything you do against them generates brave for them. By the time Galahad goes she one shots the entire rearline, if unlucky Arthur uses excaliber and well insta kills the middle row.
Pretty much got so fed up with it I undid the entire turn and used all 3 ancient heroes against them with -1000 dmg items and Atlas's hyber barrier, Enkidu's wall of Babylon and fnished them off with Gilgamesh.
That Britannia fight is one of the harder in the entire game. Hardest are of course in Shambhala.
Sometimes you just have to bring your A-team. Ancient heroes, Billy the Kid (Bandits is really nice for mass extermination) can do wonders. A dead enemy can't damage you or generate brave.
Draining brave is rather inefficient to deal with foes. A better method is simply using attacks that do not have type advantage, since that will greatly reduce the amount of brave opponents get. That might not be easy to pull off, but usually arts (hardly ever useful AOE attacks though), and bows can be extremely useful for that. Not only do enemies not get brave in such cases, you can get a boatload of brave yourself as well, if you damage foes without type advantage. Throw attacks are usually weak, but don't have many type advantages either.
The other thing you can do is put some brave bait on the front lines. If the enemy attacks with type advantage you're the one that is getting the brave. You can use sturdy units like Rasputin for that for instance.
