Unit Feat Mod minus 100% wth?

[ЧPOG]

I attacked alien wildlife in mountains with infantry+MG squad and got weird UNIT FEAT MOD - 100% attack roll nullifying penalty.
For what??
Otherwise, I had rather good chances to hit the target.
https://ibb.co/vykNtk2

UPD: not sure, maybe it's alien's feature Absorption. Anyone knows something detailed? https://ibb.co/Ghcfvg3

[Pain]

Yeah, it looks like you need something with more punch. Your unmodified attack was 109 and the unmodified health of the creature is 286. I think you need a light tank with at least 300 attack score or something.
What would be helpful in the tooltip is the chance for absorption to trigger, because it says it does not necessarily need to trigger.