[MotW] Creeping Cold + Extend Spell = ?

[Suldulin]

also still don't forget you're still saving for the 5th and 9th level as if it was 2nd (fort: half) personally I believe there are much better choices for 9th level, mass heal verses undead, elemental swarm, Heightened Finger o' Death, ShapeChange, repeated(T&B) FireSeeds. . . etcetera etcetera

and also better choices for 5th level: Memory Rot, Vine Mine, Inferno(from Magic of Faerun), Kiss of Death (MotW), Animal Growth, Awaken, Commune with Nature, Control winds, Summon Nature's Ally V, the Transmutes, for example

 

[Voadam]

I agree with Vaeron, it is unbalanced but under the rules each extend increases the duration by 3 rounds and under the description each round is cumulative.

Even if it was only cumulative for the first three rounds and did 3d6 each round after that it is still 9d6 for each spell level increase.

Think of a hit and run druid villain casting it on a PC then running away to come back for the now frozen opponent.

Can you post the exact spell text?