How do you counter this unit. I was obviously winning a game then all all of a sudden polluted and a turn after another... They are 40 nora with 5-6 cooldown and init. So they are in battle really quick. Then a dusk creeper chilling in the back getting the nora globes...
Block him with a relic if you can since he can only deal disease damage. Use stealth,cc or better positioning to take advantage of short lived if you can.
Depends on the map and BG. Essentially, you need to choose between backing off and forcing the Martyr to be bad value or pressing the advantage that forced out the Martyr in the first place. A lot of factors go into fighting this kind of unit. Also, what @D4rkSteel said.