This affects _ALL_ Units, and you will generally see Units are about 1 stat point bigger on average.
Must Attack got a further buff such that they are now 2 stat points bigger than before.
We also brought back Cannot Block as a credible alternative to Must Attack, since some decks prefer to avoid the risk of mandatory combat. This ability is similar ( but slightly less ) in point value to Must Attack.
These balance changes also opened up a large design space for over 100 new Units, many of which fill existing "holes" that players have been feeling during draft and deckbuilding.
These new Units are _not_ in this balance patch. We anticipate we can begin releasing the new Units in about one week, and with over 100 to work with, we think that will last quite a long while :)
As always, balance is subject to change as we inspect the math and the gameplay logs. Manacaster's game balance is handled by a "point balance" algorithm that ensures all cards properly represent an equal sum of Costs and Benefits.
Keep on 'casting!
-- Admins