FeoTun is a rare Runeword created by combining a Feo Rune of Ritual and a Tun Rune of Invocation.
How to Create FeoTun
You can create FeoTun by adding the rare Feo Rune of Ritual and the magic Tun Rune of Invocation to a two-socketed Helm, Chest Armor, Pants, or Two-Handed Weapon.
Feo - Become Injured or Crowd Controlled. (Cooldown: 10 seconds) (1000)
Tun - Invoke the Rogue's Stun Grenades, Stunning and dealing damage to enemies. (100)
Overflow
When FeoTun overflows, you receive the Tun Rune's overflow effect (Increased Grenades Spawned) 9 times.
Overflow occurs when your Ritual generates more Offering than required for the Invocation. The overflow effect is proportional to the amount Offering overflows.