In the story of Exodus the ten terrible plagues that God brought onto Egypt are his mighty acts of judgement. [meaning judgemt will fall] God used the plagues to punish the egyptians. They are called...
Shadrach, Meshach, and Abednego (I think in the book of Daniel, chapter 3)
God not making Abraham sacrifice his son, Issac, to show his love to God (Genesis 22:1-24)
The acts of God during the flood included the destruction of all air breathing creatures that weren't included among the passengers of Noah's Ark. It also may have included all those that didn't...