Necrogiant (Painkiller game series)

Necrogiant - the first boss you fight against in painkiller. He appears at the last level of the first chapter and is the first general of Lucifer.

Strategy
This first boss is pretty straightforward. Just hit him with everything you've got and avoid his attacks. The shotgun is the best choice for him, because while the stake gun might do more damage per shot, the shotgun has over double the fire rate, and his large body catches most of the shotgun shot; this translates to a higher DPS from the shotgun.

The Necrogiant's spells include slamming the ground to summon minions, conjuring spikes from the ground beneath Daniel, meteorites, and a tornado. The minions can be killed en masse via sawblades, just like skeletons or evil monks. His physical attack is a simple arm swing that does massive damage and has a insane range, it will toss Daniel through anything, even roofed gravestones. His move-set slightly changes after the player depletes half of the Necrogiant's life, which is signified by breaking the chains around his upper body. He will stop summoning minions, and will start using the tornado, arguably the nastiest and most dangerous spell he has. The only way to escape this spell is to go under one of the gravestones with a roof; failure to do so may kill the player almost instantly. Finally, needless to say, stay away from his legs; they sting like the dickens.

Trivia

 * The Necrogiant may be the first boss but his spells and the tornado make him harder to survive than the next two generals.
 * The Necrogiant is not a demon but some sort of a hellish abomination.
 * Armor can be found by going to the grave on the left at the start of the fight.