Niv-Mizzet, Guildpact

Convoke, Flying, Prowess, Dredge {3}
Fell the Gods — When Niv-Mizzet, Guildpact is
dealt damage, if it is untapped, you may deal that
much damage to target player and target creature
that player controls.
If Niv-Mizzet, Guildpact would be dealt damage
by a source you control, you may reduce that
damage to 1.