This page has some mulligan statistic for FN-2199 from Faltering Allegiances:
These are the odds of getting a card you want given a number of cards in your deck and a number of cards mulliganned
These are the odds of getting a weapon based on numbers of cards mulliganned, with the addition of FN-2199 from Faltering Allegiances
These are the odds of getting a weapon to your hand assuming you failed to draw one with your first hand, without the use of FN’s ability
These are the odds of getting a weapon to your hand assuming you failed to draw one with your first hand. You can use this to work out what the odds of getting a weapon with mulligan and FN combined are, given you’ve failed on your first attempt.
echobase 