Quote Originally Posted by Matsaya View Post
The nice thing is that the first tendrils does not need to be lethal.
Bolas's citadel + tendrils -> you pay 4 life, but win 4

If you add other spells, besides the initial requirement of being able to pay 4, each tendrils help you to cast more spells.
That's a good point, because then something like a double Tendrils can win from "lower" starting life, for example.