I want to know how i can deafeat medusa without losing units converted to stone.

Is beacause i almost deafeat her but i lost against them

This should be in the Stick War 2 section, but if you want to cheat to not let your units be petrified, garrison them before Medusa. However the units that you get (if you play it legitimately) are enough to stop her.

i do that but they didn`t reached the castle the last time that i played only 1 miner did it all the rest into stone

You can defeat Medusa by just using the additional reinforcements given to you but ill suggest you do a spearton and albow spam also giants as Medusa can't petrify Giants except for the part where Medusa will petrify everyone

lol i have idea!
my army was in the castle (2giant 1magikill 2merics & a lot of archidons), i was attacking medusa's statue with just 5 archidons and 2 spearatons. when medusa go out from the castle they kill just my archidons and my 2spears but not my 2giant and my magikill.. who are in castle , it's like a glitch ;) just do it and you will win
(sorry if you don't understand me :P)