Name a cool way to permanently kill a rakshasa

[rgard]

Feed it to a dog god.

Dog god ate my rak'stash'a, man.

 

[rgard]

1. Flesh to stone.
2. Rock to mud.
3. Break out the rolling pins.
4. Mud to rock.
5. Stone to flesh.

You'll have to feed it daily to keep it from dying and reincarnating.

 

[xxXEliteXxx]

I'm about 3 years late to the party, but I believe the Helm of Seven Deaths from Mordenkainen's Magnificent Emporium [Pg. 69] can capture a soul and as long as none of the Helm's powers are used then the Rakshasa cannot come back. It even states "A dead creature cannot be returned to life while its soul is captured in this manner."