This fourth part of Nine Inch Nails' dark ambient series was the final part released twelve years ago. Once again, it consists of nine separate tracks with running times between two minutes and six minutes. The songs are overall more coherent, detailed and vivid than tracks from the three predecessors. This fourth part is easily the most diversified, dynamic and entertaining. It's still experimental at all costs but more accessible than its predecessors.

''28 Ghosts IV'' is probably the most imaginative and memorable song of the bunch. The song features acoustic guitars evoking American country music, gloomy electric guitar riffs and only few electronic background samples. This song would fit perfectly on the soundtrack of an experimental western.

Another great tune follows immediately after with ''29 Ghosts IV'' that focuses on vivid electronic music with eerie sound effects that combines the band's accessible and experimental sides in one single tune.

''31 Ghosts IV'' is heavy and noisy with domineering electric guitar sounds and uneasy electronic effects that make for a nightmarish alternative rock vibe. You shouldn't listen to this song when being in an anxious, negative or nervous mood.

''32 Ghosts IV'' blends in fluidly and includes samples that remind of a patient on a respirator in a hospital that sound quite creepy.

After a much diversified fourth part of the series, the final ''36 Ghosts IV'' completes the tetralogy on piano sounds that are fittingly both appeasing and uneasy. This approach goes back to the very first song of the first part of the series and appropriately comes full circle. It shows that despite numerous changes, the concept combining these two extremes is the guiding line of these four initial releases.

As mentioned earlier, this fourth part of the series is dynamic, entertaining and imaginative. It ultimately qualifies as the most accessible, coherent and recommendable part of the unusual series. If you don't have time to listen to all four parts with a total running of one hundred and ten minutes, you can simply check out this fourth and final part to verify whether this uncompromising project could be of any interest for you at all.

On a closing side note, there are two bonus tracks that are particularly hard to find. ''37 Ghosts'' has an epic, mysterious and spiritual vibe that clashes with chaotic, fast and noisy electronic samples. ''38 Ghosts'' combines numerous interesting electronic samples but lacks coherence, flow and structure.

Please note that this unusual series would only continue twelve years later with the calm and soothing ''Ghosts V: Together'' and the dark and unsettling ''Ghosts VI: Locusts''. 

Final rating: 80%

Ayreon's Timeline is the best example for a perfect greatest hits collection. This starts with the wonderful cover artwork that references past releases without looking bland. It continues with a gigantic booklet and poster that offers everything a fan wants to know. Even the quality of the physical material used here is second to none and looks amazing in any collection.

The Dutch progressive rock mastermind summarizes his eclectic career perfectly. This small boxed set includes three discs with running times of seventy-four, seventy-six and seventy-seven minutes. The tracks are presented in chronological order. Some of them have been modified slightly to blend into one another and make for coherent, entertaining and fluid transitions. Track lengths vary between one minute and a half and twelve minutes and a half. Acoustic versions meet single edits and full-fledged progressive metal epics. The final song on the third disc is a brand new tune that serves as an atmospheric epilogue to the first fourteen years of Ayreon's career and can be considered one of Arjen Anthony Lucassen's best songs ever.

This boxed set also includes a DVD with about two hours of extra material. Some of it has been released on multiple outputs throughout the years but die-hard fans even get some new material as well. This DVD includes rare live recordings, concise teasers and exclusive looks behind the scenes. This DVD gives the evocative progressive rock music of Ayreon rarely seen visual components since Arjen Anthony Lucassen very rarely played concerts back in those days and didn't give a whole lot of interviews either.

Sincerely, there isn't one thing to complain about this beautifully crafted greatest hits boxed set. If there were only one Ayreon album you should own, this is the one you should go for. Timeline is perfect for die-hard fans, occasional listeners and complete newcomers alike. Anyone who likes space-influenced progressive rock music should own this output that offers value for money.

Final rating: 100%

Nine Inch Nails' third Ghosts record consisting yet again of nine tracks varying between one minute and a half and four minutes in length is different from the first two parts in this unusual series. The first part was unconventionally experimental while the second part was almost appeasing and calm. This third part can be situated somewhere in between these extremes. Uneasy distorted guitar sounds meet dynamic darkwave passages and atmospheric piano parts in the different songs.

If you take the songs one by one, they sound quite coherent. ''22 Ghosts III'' for instance would be the perfect song for the soundtrack of a gloomy horror movie as you can picture a figure clad in shadows wandering through the dark hallways of an abandoned asylum. ''24 Ghosts III'' focuses entirely on danceable electronic music with a few vocal samples and one would rather picture an ecstatic crowd celebrating an Electronic Body Music band on the stage of a gothic festival. ''27 Ghosts III'' seems to offer an uneasy ride through a tormented mind with heavily distorted guitar sounds and menacing rhythm patterns.

While the tracks sound interesting one by one, the only element that connects them is the fact that you have to expect the unexpected. This third part of the Ghosts series offers some gems but the song writing isn't as coherent as in the two preceding parts. It's all over the place and hard to digest even by Nine Inch Nails' experimental standards. 

My suggestion is to listen to this part of the series a couple of times, choose your favourite tunes for a diversified playlist and listen to the more coherent predecessors instead.

Final rating: 70%