If you’re one of the few people who still hasn't got round to watching the last Game of Thrones series, then be warned: spoilers ahead.

Season six of GoT had some of the most spectacular special effects ever seen on a TV show, but probably the most memorable of these was seeing Cersei blow up the Great Sept of Baelor by igniting the wildfire beneath King’s Landing.

The resulting fiery green explosion and ensuing carnage were a sight to behold, and now GoT’s VFX studios, Mackevision and Rising Sun Pictures, have released a couple of short videos showing how the effect and its aftermath were created.

The clips also feature some of the other FX-heavy scenes from latest series, including the one of Daenerys Targaryen’s grand fleet of ships sailing across the Narrow Sea as her trio of dragons swoop overhead.

The videos show the enormous number of layers and effects that go into creating the Game of Thrones world. With so many architectural wonders found around Westeros and the other locations, a huge number of shots have digital images added to them; the cast perform many of their scenes standing in front of green or blue screens.

Some of the best moments show how a relatively small amount of people can be made to look like hundreds of rowdy citizens by digitally adding extras. Check out the motion capture actor wearing the Oculus Rift; by using VR to show what is happening in the scene and where to look, his responses should be more authentic. These movements can then be replicated by members of the CGI crowd, making the final clip look incredibly real.

For those who haven’t already seen it, an in-production teaser for Game of Thrones’ seventh season was also recently released. You can watch it below, then start counting down the nine long months until the new episodes air.