UNDER THE OAK hailing from Fredrikstad, Norway were formed in 2017. The Thrash Metal outfit released with "Rattus Norvegicus" their second full-length album. It has a length of more than 55 minutes, and it was released via Italian Death, Thrash, and Black Metal specialists WormHoleDeath. The second album by UNDER THE OAK continues where they had left off with the debut "Ripped Up By The Roots" in 2020. The opener "Total Trash Metal" has all the ingredients of traditional Thrash Metal: speed, aggression, tight guitar riffing, and relentlessly hammering drumming. The vocals cover the range of classical Heavy Metal vocals from being harsh with lower notes to highly pitched notes and screams. "Total Trash Metal" is a good opener, hinting to the things to come for the next hour. It is also the official video release with the YouTube link given below.

While the opener is a fast Thrash song, "Running With Scissors" is a mid-tempo track with more focus on melodies. The riffing is catchy, and the vocals go with the melodies. The track has some changes towards a slow and measured tempo for the chorus parts and they are driven by the lead guitars and the double-bass drumming. The lead guitar solo is very comprehensive and highlight of the song. "Our Own Choice" has a powerful start with heavy riffing, which has some oriental vibes. It is a mid-tempo track with switches to a higher pace during some parts with again lots of double-bass contribution. "Inner Demon" is a song for the pit: fast, aggressive, with flesh-ripping riffs during the verse parts, and more melodic mid-tempo chorus parts. The guitars driving the track forward, including a very contributing lead guitar solo. "Walls Of Pain" is also one of the faster tracks, where the melodies of the riffing are the focal point of the song. It is technically a highly comprehensive song. From the mid-tempo break onwards, I got a bit lost as UNDER THE OAK put a lot of different style elements together. I think, keeping the middle part simple would have made "Walls Of Pain" to a great song.

"Loyal To The Core" has a powerful start with heavy, but catchy riffing and crunching bass lines at mid-tempo. The chorus part is a simple sing-along of the title. The middle break is also kept simple, and I have been missing a lead guitar solo here. However, "Loyal To The Core" is all about the message. "Bangkok Haircut" is in principle a crushing and aggressive track with tight riffing, cool bass lines, and direct lead guitar parts. From the instrumental contributions, it would have been a great Thrash song, if the vocals were more comprehensive including the lyric lines. I did expect a bit more than repeating the vocal line "Bangkok Haircut". "Everything Became Nothing" starts with an acoustic guitar intro transitioning into a Thrash ballad at a slow and measured tempo with epic melodies. The melodies suit perfectly to the vocals and Jostein Sandaker can show his remarkable vocal range during the ballad-esque part. There is a bridge towards a high-speed part of the track and the guitars sound pretty much ARCH ENEMY inspired during the bridge. The middle part of the song is Thrash Metal riffing at insane speed, before the track circles back where it all begun. "Everything Became Nothing" is one of the album highlights.

"Pandemic" starts with an extended instrumental part, before the vocals join in. It is a pacey track during the verse parts and a mid-tempo banger during the chorus parts and the break. The lead guitar solo is once again the highlight of the track. The title song starts with another crunching bass line, before it transitions into a fast and aggressive Thrash song driven by the sharp riffing and the hammering drums. It is a fast song for most of the time, with some mid-tempo parts during the break and towards the end. "Rattus Norvegicus" is another album highlight. "Echoes Of A Distant Battle" is a mid-tempo track with plenty of traditional Heavy Metal vibes and cannot quite keep up with the rest of the album. The album closes with a DESTRUCTION cover of the classics "Mad Butcher" and "Bestial Invasion". The instrumental part is very authentic with some own notes, unfortunately the vocals do not match the aggression of the original.

UNDER THE OAK deliver a good traditional Thrash Metal album. "Rattus Norvegicus" shows some of the best features of classical Thrash Metal and indicates why the genre is still so popular after almost 40 years. Strengths of the album are the guitars, the riffing and the lead guitars as well as the bass lines and the drumming. I was missing drive and aggression in the vocals at times. A few songs sounded a bit unfinished from the songwriting point of view. A little bit of tightening up would have benefitted the album. Overall, "Rattus Norvegicus" has its moments and Thrash Metal fans will surely dig the album and look forward to some insanity in the pit when the album songs are being played live.