Chain Effect

Chain Effects are those effects that can jump/transfer to multiple nearby enemies. Chain Effect Abilities are most effective when used near a group of enemies. The larger the group the more effective the Chain Effect will usually be.

Also See:
Area of Effect
Multiple Targets

The Following Is A List Of Each Class' Skills That Have Chain Effects:

Demon Hunter Skills That Have Chain Effects
Marked for Death (Contagion)
Spike Trap (Lightning Rod)

Monk Skills That Have Chain Effects

Exploding Palm (Essence Burn)

Witch Doctor Skills That Have Chain Effects

Haunt
Zombie Charger (Undeath)
Firebomb (Flash Fire)
Firebomb (Roll the Bones)
Locust Swarm

Wizard Skills That Have Chain Effects

Frost Nova (Shatter)
Electrocute
Explosive Blast (Chain Reaction)
Arcane Torrent (Cascade)