Elemental massacre or assisted attack?

[DMGInterference]

This is Element Massacre’s power modifier:

@Killerdog

However, just one other of the same element and it’s stronger than a normal AoE.
1 monster = 0.045
2 monsters = 0.25
3 monsters = 0.45
4 monsters = 0.57
For reference, ultrablaze is something like 0.16.

Also:

@Killerdog

Assisted hit all is the same strength as the standard hit all when you have 1/4 of the element (just the user). It becomes double strength with 4/4. I believe it’s +30%, +60%, +100% but I need to double check that.

If I am now wrong, this means fullpower 250sec Assisted All has a 0.32 multiplier and its therefore weaker than 3/4 target Element Massacre.
The Assisted power modifier is uncertain though, so it may not be right. Or maybe I am just stupid .