Diablo – What on hit effects are in Diablo 3

• Snared: Your character is slowed down. The magnitude of the slow effect varies depending on what's doing the snaring.

• Rooted: Unable to move from your current position.

• Attack Slowed: You swing your weapons more slowly.

• Chilled: Snared + Attack Slowed

• Frozen: Mostly the same as stunned, but certain skills, like the Wizard's Frost Nova's Shatter Rune, cause frozen enemies to behave differently. Frozen enemies leave no corpse.

• Immune: Immune to whatever status effect you're trying to apply. This can be knockback, stun, snared, or any other status effect, depending on the individual in question. Bottom line - one or more of your status effects isn't "sticking", so to speak. Unlike Diablo II, no monster in Diablo III is supposed to be immune to a damage type (though they might have high resistances).

• Knockback: Physically moves the target away from the origin of the attack.

• Stunned: Rooted, and unable to attack.

• Charmed: Fight other monsters instead of the player

• Feared: Running in fear, unable to take action or control direction of movement.

For attacks that hit multiple enemies, Yes.

I haven't explicitly tested all on-hit effects. I will update this answer as I do.

Life on hit: Confirmed. With a +2 life on hit weapon equipped, I often saw healing popups of +6, +8, +10, etc while using area attacks that hit multiple targets.

Chance on hit to fear: Confirmed. Using Deadly Reach I saw two enemies get feared and run away.