• Company using non compete clause to stop me from going to any other company.

I joined my company 3 months ago as a software developer, the company makes real money games where people pay real money to play games and get real money in return.
I did not like the work culture and the way they treat their employees, so I officially mailed a resignation letter stating that I will serve my notice period and will leave after that.
The company tried to lure me back my promising all kind of things and stating that they will agree to all my terms.
But I didn't want to stay so I told them that I will leave.
Now they bring out the contract and telling me that I need to tell them which company I am going to and they will sue me if I go to any company which is related to gaming.
They are harassing me with mails and through other employees that I should tell them the name of the company I am goin to and will end my career by suing me if I join any other company.
I want to know does this non compete clause really gives them this power to stop me from going to any other company which is in the gaming domain. And what steps should I take to ensure that I am not sued regarding this and can carry on my career.
The clause is : 
The Employee agrees that he shall not, as an individual, employee, consultant, independent contractor, partner, shareholder, member or in association with any other Person, except on behalf of the Company, directly or indirectly, as long as he is engaged with the company or for a period of 18 months from the First Closing Date (whichever is earlier) (“Restricted Period”), own, develop, manage, establish, engage in, operate or cause to be operated or consult in a business that competes with the Business of the Company (“Competitive Business”) or carry on the Competitive Business or solicit for the Competitive Business, any customer or target customer or key personnel or supplier of the Company or otherwise use its knowledge or influence over any customer or target customer or key personnel or supplier to the detriment of the Company. The Employee agrees and covenants that while employed by the Company and for a continuous period of 12 (twelve) months following termination of his/her employment in the manner set forth above the Employee shall not directly or indirectly through any Person, entity or contractual arrangement engage or be interested in any business anywhere in the world similar to the Company’s Business, as it may exist from time to time after the date hereof, or perform management, executive or supervisory functions with respect to, own, operate, join, control, render financial assistance to, receive any economic benefit from, exert any influence upon, participate in, render services or advice to, or allow any of its officers or employees to be connected as an officer, employee, partner, member, shareholder, consultant, act on a work-for-hire or outsourced basis or otherwise provide any services for, any business, Person or entity that competes in whole or in part with the.