I received 200K foreign gift. How can I transfer back to US? Is there any tax implication? What forms I need to file?

Thanks

In the U.S. the receiver of the gift does not pay any tax. You will need to file Form 3520.
Read Your U.S. Tax Return: The U.S. Gift Tax (http://taxipay.blogspot.com/2008/03/us-gift-tax.html)