There are a ton of speculative theories on Willy's purpose, but it's basically impossible to know ,even if there was a bot, it's highly unlikely that it was solely responsible for the rise in price.
To Foxbitcoin Sigh.... its the mass's and mass's of people like you that are uneducated and unwilling to do the research that makes the understanding of bitcoin really difficult ...
Like the blind leading the blind (uneducated leading the uneducated) ... leads to more misunderstandings...... here are a few articles on the topic of WILLY BOT and other manipulation trades ....
https://willyreport.wordpress.com/2014/05/25/the-willy-report-proof-of-massive-fraudulent-trading-activity-at-mt-gox-and-how-it-has-affected-the-price-of-bitcoin/http://www.coindesk.com/bot-named-willy-did-mt-goxs-automated-trading-pump-bitcoin-price/Sidenote: take the time to actually learn more about the reason why bitcoin reached 1200$/btc in the first place and the realization that bitcoin is a contract(commodity) / non tangible asset account which is used to transact between the exchange of a good and currency not currency itself ... look through my past posts to read more into it...
Addition: to Cconvert2G36 , in some part yes it did bring in the "lemmings" that decide to jump off the cliff with the crowd fueled "hype" towards $1200 ... but it was mostly due in part to WILLY BOT and other manipulation
since there was approximately addition of thousands of "investors" that poured in their money into bitcoin.
Addition: to gentlemand You are correct
Mtgox WAS THE BIGGEST player... by a FAR FAR FAR MARGIN ... at the time they had a market grasp of atleast 70-80% at the time of the markets volume of trades if not even more at the hype due to "willy bot and manipulated trades"