In a lot of cases, it's basically the white Craterhoof BehemothCraterhoof Behemoth (sorry, Moonshaker CavalryMoonshaker Cavalry)
White sees itself as the good guy, so it doesn't like "shooting first," but as soon as the opponent's creature takes a swipe at either the white mage or his or her creatures, white is in the clear to destroy it
If the creature you control is an illegal target, you won't put two +1/+1 counters on it even if you have delirium
Considering this, we use almost anything we can use to protect them
Some are triggered, and others are activated abilities
Blasphemous Act Rounding things out, we have Blasphemous Act, a card I see at least 1.5x per game