From Dota 2 Wiki
| Faerie Fire|
|The ethereal flames from the ever-burning ruins of Kindertree ignite across realities.|
- Faerie Fire does not stack in the inventory. Each of them requires its own slot. Their attack damage bonus does stack.
- Faerie Fire is not shareable and cannot be used on allies.
- Interrupts the user's channeling spells upon cast.
- Faerie Fire is often purchased as a ranged equivalent or cheaper substitute for Quelling Blade. It is generally good on heroes who intend to farm and get last hits, but start out with low damage.
- For the mid-laner, Faerie Fire can create an advantage over the enemy, as well as save him from a gank.