2019 release. Infest the Rats' Nest is the 15th studio album by Australian psychedelic rock band King Gizzard & the Lizard Wizard. The album sees the band exploring more into heavy metal, which the band had only ever briefly touched upon on previous albums. Infest the Rats' Nest was recorded with only three of the band's usual seven-man lineup. The album showcases influences completely derived from heavy metal music. The album mixes thrash metal with the bands signature garage rock influenced guitar tones along with their psychedelic and space rock sounds. The album makes consistent use of double kick drumming influenced by heavy metal pioneers Motörhead. The albums themes include ecological disasters and aliens migrating to different planet in which frontman Stu Mackenzie stated was based on events that are happening in real life. Mackenzie also cited the albums strong thrash metal influence derived from bands such as Metallica, Slayer, Exodus, Overkill, Sodom and Kreator.