From HoNWiki

Tablets, or more commonly called Runes, grant various powerful temporary effects when picked up.

Double Damage Effect +100% Base Damage Duration 45s	Haste Effect Grants unit max movespeed (522) Duration 30s	Illusion Effect Spawns two images that take 300% damage and deal 35% damage Duration Images last 75 seconds
Invisibility Effect Grants invisibility with a 2 second "fade time"* Duration 60s or until invisibility is broken	Regeneration Effect 6% Health regeneration per second 10% Mana regeneration per second Duration 30s or until Health and Mana are full, or until unit receives any damage

Runes can also be picked up with an empty bottle. Once bottled, a rune may be used at any time or stored up to 2 minutes, at which point it is automatically used regardless if you are dead or alive. When a rune is used from a bottle, the bottle is completely refilled.

* The first 2 seconds of the Invisibility rune is independent from the actual invisibility status buff. During these 2 seconds, you can perform any action before the actual invisibility is applied. After those 2 seconds, any action performed will break invisibility.

[edit] Rune spawning

Runes spawn at either one of two locations on the map, every two minutes, starting at 2:00 on the timer.

Only one rune may be on the map at any given time. Having a rune bottled will not prevent a rune from spawning.

Screenshots to show rune locations on the maps

	Forests of Caldavar	Watchtower	Darkwood Vale
Top/Left Rune
Bottom/Right Rune

[edit] See Also

Using Runes