Hedge fund manager J. Kyle Bass has been shorting the Texas-based REIT United Development Funding (UDF), which he calls a "Ponzi-like real estate scheme" that targets mom-and-pop retail investors. 

Bass is known for cashing in on shorting mortgages before the 2008 crash, and then again shorting biotech stocks just before that sector took a dive, Business Insider reports. (So ignore him at your own risk.)

UDF invests in homebuilders and land developers in select markets across the country, and, according to its website, has "a reputation built on integrity and performance.

Yet, in December, Bass published reports slamming the REIT on investing website Harvest Exchange, under the superhero-esque moniker “Investor For Truth.” Since the reports, shares have crashed over 40%.

Bass alleges UDF is paying old investors with new investors' money and covering it up with real estate-backed loans through a web of UDF-controlled entities.

“UDF management claims that its business is sound. Using cash flow from new investors to pay old investors is not sound,” Bass writes on his new website, udfexposed.com.

UDF shot back at Bass, accusing him of unlawfully manipulating their share prices in a December SEC filing.