Blizzard fully acknowledged Hearthstone's bot problem last week, delivering a fierce banhammer to thousands of bot accounts. The creator of many of those bots has seen the way the winds have blown and has decided to pack it in.
Crawlerbots, creator of the Hearthcrawler bot, posted the following on his website this morning:
This is our last official announcement. The recent ban wave in Hearthstone hit a lot of users.
After discussing this with Blizzard, it’s clear we have to take off our services/products now. Please note that we’re not going to be commenting further on this.
Thank you all for being part of our community. We are very sad about this but you also know botting is against the rules and we all knew that the day when our products doesn't work anymore would come.
With tears in our eyes we have to say bye.
The whole team of Crawlerbots.
Blizzard previously stated that further incidents of cheating would not be tolerated. They stated that offending accounts would be permanently banned without warning.
Today's events, however, do not spell the end of bots in Hearthstone. Ars Technica points out that several other bot program exists. Among them is a program that analyzes Hearthstone decks based on analysis of select cards, though that program's creators note that they will not release their program to the publi.