Nikolaj Coster-Waldau knows how to play with Game of Thrones fans.

The actor who plays Jaime Lannister on HBO's mega-hit fantasy series posted a photo to Instagram with just enough teasing info about what's coming up in Season 7 to keep it from passing into outright trolling.

But it's definitely borderline trolling.

Coster-Waldau posted a selfie of himself next to some wine barrels with the caption "Game of thrones season 7. Will be explosive. #got7 #hbo#whatdoesitmean?" The post is geotagged "Casterly Rock, Westeros," the ancestral home of the Lannisters.

Coster-Waldau likely wants us to think that the barrels are full of wildfire, the unquenchable green fire memorably deployed at the Battle of Blackwater Bay and the Great Sept of Baelor, which was destroyed last season after Cersei (Lena Headey) decided to kill all her enemies in one fell swoop. The show has not yet visited Casterly Rock, but there's footage in the trailers that shows Lannister forces fighting the Unsullied in a castle hung with Lannister banners, so we're going there this season. And Coster-Waldau seems to be teasing that the battle will end in wildfire.

Game of thrones season 7. Will be explosive. #got7 #hbo #whatdoesitmean?

A post shared by Nikolaj Coster-Waldau (@nikolajwilliamcw) on

Like the Targaryens, Lannisters love wildfire. Tyrion (Peter Dinklage) and Cersei have both deployed it, and they're the most likely candidates to use it again, with Tyrion seeming slightly more likely in this case. In the second Season 7 trailer, Grey Worm is on a boat that appears to be approaching a crack in a rock wall. That crack is presumably an opening to Casterly Rock's sewer, a place Tyrion knows well since he was put in charge of them when he was younger. Most likely, Tyrion is directing Grey Worm (Jacob Anderson) and Daenerys' (Emilia Clarke) Unsullied army into the sewers, allowing them to sneak into Casterly Rock and launch an explosive attack.

But Nikolaj Coster-Waldau knew that this kind of speculation would happen in response to his post, so maybe he's just trolling fans with something that could happen but won't. The cast has definitely done that before.

We won't know for certain until Season 7 returns on Sunday, July 16 at 9/8c on HBO.