Zynga Inc (NASDAQ:ZNGA - 2.94) has followed the broader market lower today, having shed about 4.6% during the course of the session. Nevertheless, the stock has seen a flurry of call activity, as roughly 44,000 contracts have traded so far, almost doubling the equity's expected intraday call volume. By comparison, around 9,300 puts have changed hands.

However, not all of this call volume may be of the bullish variety. A closer look at the data shows that a block of 14,600 contracts was sold at the September 3.50 call for $0.43 each, while a matching number of contracts was bought at the September 4 call for $0.36 apiece. Meanwhile, today's volume at the 3.50 strike has exceeded current open interest levels, while implied volatility has ticked higher at the 4 strike -- hinting at the initiation of new positions. In other words, it's possible that one trader has constructed a bear call spread on ZNGA for a net credit of $0.07 per pair of contracts.

By utilizing this neutral-to-bearish strategy, the speculator is betting on the stock to finish at or below $3.50 by September expiration -- rendering both options worthless, and allowing him to pocket the net credit received, which represents the maximum reward on the play. However, he can still profit if the equity closes below the breakeven rail of $3.57, or the sold strike plus the net credit. Conversely, his potential risk is capped at $0.43 (difference between strike prices, minus the net credit).

From a broader sentiment scope, call players have been taking a more "vanilla" approach to the online game guru lately. Data from the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX) shows a 50-day call/put volume ratio of 5.77 for ZNGA, confirming calls bought to open have outnumbered puts by a margin of nearly 6-to-1 during the past 10 weeks. This ratio ranks in the 88th annual percentile, conveying traders have been picking up bullish options over bearish at a faster-than-usual pace.

Technically speaking, ZNGA is down nearly 75% on a year-over-year basis, but has gained some momentum in 2013, climbing approximately 24% year-to-date. Time will tell if today's strategist will end up retaining the premium received from his September bear call spread.