Is re-rolling a "modifier"

[Battlehammer Jelly Thyme]

Be'lakors warscroll reads

Shadow Form
Ignore modifiers (Positive or negative) when making save rolls for attacks that target this model.

So I read this as he can not benefit from Mystic shields (+1 to save rolls)
But if I used a re-roll failed save rolls ability would this be allowed or does a re-roll count as a modifier?

[EMMachine]

No, re-rolls aren't modifiers. They actually happen before you check for Abilities which need a unmodified value.

[Liquidsteel]

1 hour ago, Battlehammer Jelly Thyme said:

Be'lakors warscroll reads

Shadow Form
Ignore modifiers (Positive or negative) when making save rolls for attacks that target this model.

So I read this as he can not benefit from Mystic shields (+1 to save rolls)
But if I used a re-roll failed save rolls ability would this be allowed or does a re-roll count as a modifier?

Rerolls are not a modifier, core rules state that re-rolls occur before modifiers are applied.

[Battlehammer Jelly Thyme]

Great, Thanks for the feedback 😊