Straddle Calendar

STDCSTDC-E2_E1-X1

Buy far-dated straddle, sell near-dated straddle (same strike).

Near Expiry (E1)

Far Expiry (E2)

Strike X1

Pure forward-vol play: long vega in the back, short vega in the front. Profits if forward vol expands.

Pick two expiries and 1 strike to build the combo.