Shadow (element)
Offense: A lot of shadow damage comes from damage over time effects and your pet.
Defense: Outside of your pet taking damage for you, shadow spells also let you leech hitpoints from enemies and restore your own.
Utility: Outside of various debuffs with many useful effects, shadow also allows you to use a pet which can copy abilities of any regular enemy in the game.
Shadow in combat
Outside of pure damage, the elemental resistance of all creatures also affect 
Shadow spells in other way.
Increases/decreases the duration of all shadow debuffs by 0.5% per every 1% of resistance.
Note: Since damage over time effects do damage only once in a while, it's possible the extra duration won't do anything to their damage.
| Original duration in seconds | Resistance | Penetration | Final duration |
|---|---|---|---|
| 10 seconds | +50% | 0% | 7.5 seconds (-25% from original) |
| 10 seconds | +80% | 30% (lowers resistance to +50%) | 7.5 seconds (-25% from original) |
| 7 seconds | +50% | 0% | 5.25 seconds (-25% from original) |
| 7 seconds | +50% | 150% (lowers resistance to -100%) | 10.5 seconds (+50% from original) |
If the target's resistance is over 80% against Shadow, it becomes immunne to any shadow debuffs (E.g. 
Plague).
| Elements |
|---|
 Fire Shadow Ice Storm Light Nature Chaos
|