What you were expecting to happen, and what actually happened?
Tzathoth’s skill says 7 damage and 20% devour chance but so far it’s been 100% devour over 10 tries.
What are the steps to make it happen again?
Fight Tzathoth and have him use his skill.
Do you have any screenshots or video you want to share with us so we can see the problem? Attach them to your post!
You’re on a lucky streak. Nothing for support to do here. I tried using it an it took me about 8 casts before I got a devour, so it definitely isn’t operating at 100% for me.
Unlucky lol.
He created account just to post that. I rarely see tzathoth in pvp at my level.
My issue was when I was fighting him. It wouldn’t be the first time that the AI in Puzzle Quest was unusually “lucky” while the player was not.
Yes, I was going to post it in my usual forum but it specifically said to come here to post possible bugs. So I did.
It’s not a bug, it’s bad luck. It does not devour 100% of the time. Bad luck sucks, I know.
Ok, fine. But I figure let the actual developers know there could be a bug and if it was, then they could fix it and if not, then whatever. I’m not just going to assume bad luck after 10 tries.
I fought one of them today for the first time ever and in 5 casts it devoured once. I’ve had Kerberos devour 10+ times in a row before sometimes you just get really unlucky.
It’s ok, many a long time player on an unlucky streak made the same topic. Just this morning I had a horrible unlucky streak with infernus self filling and extra turn 3 times in a row.
If you are playing with Tzathoth it is 20% chance to devour. I can’t add anything more than what has been said… it’s randomised. You can take my word that it is definitely not working against you in the sense of being unfair. You are the receiver of bad luck? 
Thank you for letting us know anyway.