Does not work with special attacks

Can you explain how you arrived at the conclusion that it does not work with special attacks?

i tested it on ffa.

i have a Monarchy with +3.5% def and it has 100 troops , no weapons tech.

Then i attacked that country with another Monarchy with no weapons tech and 102 troops on GS and the 100 troops were defeated .

Did you only try it once? There is a random factor in the attack formula.

i hate random factor

suggestion: remove random factor

How large is the random factor?

i tried 2 more , 1 was repelled.

Not sure but the guide says to oversend by 10% to have a 99% chance of success

Of course if the def bonus is only 3.5% then sending 110 troops would be succeeding most of the time against that as well.

I would suggest trying 103 troops. If the bonus is not working, you should succeed a solid majority. If the bonus is working, you should fail more than succeed. You will need to do rather a few attempts to be sure though

Thanks for help , i dont want to waste many turns and will try it again when i have some more Permanent bonus defense.

its a gaussian