In September 2015, Gaahl announced his new band, Gaahls Wyrd, who played their first live show at the Blekkmetal Festival in Norway on November 13, 2015. In regards to forming the new band, Gaahl stated:
"I'm very pleased with what me and Tom have done together. We've created a lot of good songs, but I think the difference between us is probably the reason why I've started this new band. I've made a lot of my favourite songs that I've created in God Seed and I've brought with me one of these characters from that band."
Since their formation Gaahls Wyrd has been consistently touring; their repertoire consists of selected songs from Gaahl's past projects, including tracks from Incipit Satan, Twilight of the Idols, and Ad Majorem Sathanas Gloriam by Gorgoroth, God Seed's debut album, and assorted tracks by Trelldom. They have also had a variety of guest performers on their shows. In 2016 they released footage of their debut performance. In 2017 drummer Baard Kolstad left the band and was replaced by Kevin Kvåle aka "Spektre". Guitarist Stian "Sir" Kårstad also left the following year and was replaced by Ole Hartvigsen of Kampfar for live performances. Both members quit the band for undisclosed reasons. On December 1, 2017 the band independently released a 12" hand-numbered EP titled Bergen Nov '15 and included six live tracks that were performed and recorded during their live debut in 2015; it featured Kvitrafn on vocals and playing the hurdy-gurdy as a guest for the first track. It was exclusively sold on the Vardøger European Tour 2017 with Auðn and The Great Old Ones and was limited to 1000 copies. On May 4, 2018 it was reissued and made widely available in CD format through Season of Mist. In September that same year the band also announced their signing to Season of Mist to release their debut album. The band announced a two month long European tour with Swedish band Tribulation and American bands Uada and Idle Hands called "Northern Ghosts Tour" that started on February 21, 2019 and ended on March 10th. The band's promotional single "Ghosts Invited" was released online on February 7 and revealed that the name of their debut album will be GastiR - Ghosts Invited and is going to be released on May 31, 2019; the album was recorded throughout 2018 at Solslottet Studios in Norway with Iver Sandøy of Enslaved, though most of the music was written and demoed by Lust Kilman and Eld as early as 2016. The second promotional single "From the Spear" was released on March 13. On April 16 the band released their first music video for the song "Carving the Voices" which was directed, shot and edited by Troll Toftenes. GastiR - Ghosts Invited was released on digital platforms on May 24, 2019 and physical media the following week. The band has also continued performing live and will be featured in several festivals. The band also revealed that Blasphemer of Aura Noir and VLTIMAS fame had joined the band as a second live guitarist since Ole Hartvigsen had to return to Kampfar for their live performances in support of their new album. In December of 2019 GastiR - Ghosts Invited was rated the third best metal album of the year by the American magazine Rolling Stone, and on February 7th 2020 it was nominated for Best Metal Album in the Norwegian Grammy AwardsSpellemannsprisen. Due to the outbreak of Covid-19 and the following national lockdown during spring of 2020, the Spellemannsprisen award show was cancelled until further notice, leaving the awards for best albums of 2019 – including GastiR - Ghosts Invited – unresolved.
