Darius's Bleed damage should be Physical
cause there's nothing magical about bleeding to death. Also is better for game health cause building armor against him would help against the bleed, but his 25% armor ignore would help him. Idk, i just hate laning against dar dar.
/update: to those of you complaining that it will be too strong late game, magic damage completely ignores armor and is mitigated by MR. If dar dar's bleed is physical, it will weaker at every part of the game because building armor would negate his entire kit (even if dar dar has armorpen, a small portion will be negated) whereas you could build MR to negate the bleed damage currently, but suffer from the rest of his kit. Another thing: Talon's bleed applies stacks of
for every tick on his bleed., so dar dar wouldn't be the first to do this.

should kill
instantly, because he ain't got time to bleed.
Smashes the ground so hard he leaves a dent and disorients the enemy to where they attack slower
Chucks/rolls a giant rock at the enemy that cripples them
Charges into the enemy at like 200mph
All magic damage >_<
Smashes the ground so hard it roots up the ground and makes people fly up
Charges and headbutts the enemy at like 200mph
Is so big n scary that he can trample towers, minions, and champions
Magic Damage
Charges at the enemy audaciously and reduces their armor
Magic Damage
Bashes someone's face in with a shield leap
Crashes down on the ground so hard he leaves a giant impact and damages EVERYTHING in the radius
Magic Damage
Kills people using creatures made of sandstone
Magic Damage.
Claws the sh@# out of you while he suppresses you with 5 mighty blows using his giant wolf claws
Magic damage
Throws an over sized cleaver at your face
Magic damage
Throws about 20 knives in your chest while spinning around viciously
Magic damage
being set on fire
Magic damage BUT



. Make it physical. AND DONT EVEN THINK ABOUT any nerfs/reverts. Once it is physical, then be happy with that change.
"Noxian Diplomacy will apply the passive armor shred of The Black Cleaver Black Cleaver for every tick of the bleed effect." -LoL Wiki