Sergei swore under his breath, cursing the guards, the king, the princess who'd brought them here, and whatever god he'd pissed off that day. He wanted to nurse his beer and listen to that knife-ear sing some more.
Fortunately, however, the guards were funneling and Sergei was sober. He began to devise an appropriately cruel plan.

"Elf, I've need of two more things. After that, take your cart somewhere safe from their spears." he threw another gold coin at her, to pay for the wares.

As the guards began to bang on the gate, he lifted the hem of his surcoat to his teeth and tore off a strip, messily poking it into his glass flask of whiskey.

The knight hefted his hastily made molotov, and circled around to the other side of the wagon. He reached in, and pulled out his next purchase: a large cask of lantern oil. A devilish smile split his cheeks as he took his dagger, and jabbed several holes in the small barrel's lid. Next, he hefted it in one arm, and slung it at the gate. The iron bars broke the wooden cask, splattering the black fluid on the guards outside as the lock threatened to give way to their ram.

Sergei took a lantern from the cart, and gently lit it, then used it to start his molotov.
"Hey, you lot ever take a castle?" he asked giddily. "It's a test of endurance. When you greenhorns jump the gun and charge straightaway, it never turns out well."
When the gate slammed open, and the knights broke through, he hurled the molotov like a fastball at the group, setting the oil ablaze.