Best strategy for keyword attack

[gentl]

So you know the base word, and you need to append some a special and two numbers?

-r ./rules/hybrid/append_s.rule -r ./rules/hybrid/append_d.rule -r -r ./rules/hybrid/append_d.rule

In this case i can use just mask attack with MikeStronger?a?a?a
But password can be 124MikeStronger!, mikeStronger213@2, mikestronger!44 (just random examples)
I need the way to automatically  create maximal cover of all possible variants. Of course i can use  mask file, make own rules, but may be exist some software to generate wordlist by keyword or something else which can do this task easie