Sword Art Online Re: Hollow Fragment leaps from the small screen of the PlayStation Vita and onto the PlayStation 4 complete with online play. Its handheld roots make this role-playing game undeniably rough around the edges, but give it some time, and you'll uncover a satisfying, addictive adventure that sports some nice touches here and there.

Following an alternate take on the hit novel and anime series in which players of a virtual reality game known as Sword Art Online are trapped within the software, Re: Hollow Fragment features most of the property's familiar faces. Fans will feel right at home from the start, but for everyone else, there's a lot of stuff to wrap your head around. From technical terms to backstory references, the whole thing will initially seem impenetrable to those who haven't at least sampled the source material.

Despite its inaccessibility, though, following on directly from a specific point in the franchise does allow the title to incorporate some refreshing and interesting mechanics. For example, you'll begin the game at level 100, as the playable protagonist, Kirito, is already a masterful player of Sword Art Online at this point. To an extent, this augments proceedings with a unique tone, as you won't necessarily feel like you're starting your journey as a typically amateur adventurer. Instead, you'll instantly have access to numerous well-rounded skills and attacks, and from there, character progression is yours to shape.

However, as mentioned, this set-up isn't ideal for newcomers. It can seem like you're thrown into the deep end from the word go as you're forced to understand the ins and outs of combat, exploration, and character development – and the shoddy text box tutorials don't help – but again, there's plenty of reason to persevere.

The flashy combat is one such reason, providing a fun system that becomes quite rhythmic after you grasp the basics. Mixing some traditional massively multiplayer online elements such as cooldown times and ability bars with a few real-time action mechanics like blocking and dodging, it's an enjoyable formula that perhaps works better than you'd expect. Because of its contrasting components, battles can actually be quite tactical as you switch between using offensive and defensive techniques. It's a combat system that takes a whole slew of statistics into account, yet there's still plenty of room for player skill and reactions, which gives way to some satisfyingly dynamic brawls.

Besides, just because you start off at level 100 doesn't mean that you've reached your limit. Levelling generally happens quite slowly as you grind your way beyond 100, but by utilising different fighting styles – each of which comes with its own set of abilities – you'll constantly be gaining skill points that you can use to unlock more techniques. There are entire skill trees to pick and choose from, and experimenting with different builds is an addictive aside, especially when you take abilities from other disciplines and find ways to make them work with your current loadout.

You're not alone in battles, either. There's a large roster of companions that you can partner up with, although many of these are generic non-playable characters. As such, the ones that are destined to soak up most of your attention are the girls from the source material who all seem to be madly infatuated with Kirito, and herein lies another of the title's more intriguing aspects.

By journeying with one of these secondary characters, you'll steadily increase your friendship with them, which eventually leads to unique dialogue and – you guessed it – inevitable romance. What's more, building relationships allows you to be better synced during combat, unleashing joint attacks more frequently. It's not a particularly deep friendship system, but the cast and their dialogue does help keep you invested in what is otherwise a combat-heavy dungeon crawler. Plus, the way that Kirito and the gang excitedly shout 'Level up!', complete with Japanese pronunciation, is just too adorable to ignore.

Meanwhile, if you don't fancy forming a team with a computer controlled party member, you can go online and fight alongside a friend or stranger. The online functionality's pretty basic, but it gets the job done, and exploring the world with a buddy will no doubt be an attractive selling point for fans, particularly when you're hunting and bringing down dangerous beasts together.

As for the actual plot of the release, there's not really all that much to mention. There's an overarching narrative about how the players of Sword Art Online fight to get to the final 100th floor of the virtual world and potentially beat the game, but nothing much happens on the way there. You explore each new floor, fulfil a few quests, take on the boss, and repeat. With 25 floors to conquer, it's a lengthy story but one without many twists or turns. In fact, most dialogue-driven cutscenes are more to do with the involved characters and their daily lives rather than their overall goal, and although this method of storytelling provides numerous light hearted moments that flesh out each personality, it's something that only fans of the original work will fully appreciate.

That said, there's plenty to do outside of the main story, too. Hollow Fragment on Vita introduced the aptly named Hollow Areas – slightly more challenging locations that are yours to explore at your leisure. These places are great for levelling up you and your allies, and they're packed with secret bosses and loads of good loot. Some of the most rewarding points of the release come when you find yourself exploring a dungeon on a whim, only to come across a full set of powerful equipment. It's dungeon crawling at its best, and the game provides these moments more often than not.

However, it's not all good news for Kirito and pals. Undoubtedly one of the title's biggest flaws is the fact that you can't manually save your game; your progress will only be saved automatically when you leave an area, and as you can imagine, this can potentially lead to bouts of frustration since you can be felled by groups of high level enemies during a stint of dangerous dungeon delving. To make matters worse, it's game over if your partner bites the dust during combat. While this makes sense given the source material's harsh permanent death rule, it still feels cheap when an ally is taken down because they refuse to sidestep a particularly powerful blow. Fortunately, though, these occurrences are rare, as the artificial intelligence is generally quite capable.

On a different but equally disappointing note, it's a bit baffling that you're free to create your own avatar – male or female – yet you're always cast as Kirito during story sections and cutscenes. It's a prime example of half-hearted implementation, and it's a shame that such a feature wasn't overhauled for this re-release.

Elsewhere, on the presentational side of things, Re: Hollow Fragment certainly looks like a handheld port. Textures are consistently muddy and environments are basic, but the attractive art style just manages to hold things together. Sadly, the release does suffer from framerate drops now and again in the bustling hub town, which is annoying seeing as the game's visuals clearly aren't all that demanding.

Audio-wise, most of the title's cutscenes are voiced, and the Japanese voice actors seem to do a great job across the board. Likewise, the soundtrack is enjoyable, sporting numerous catchy tunes, but it's the electro-rock battle themes that steal the show.

Conclusion

Sword Art Online Re: Hollow Fragment could afford to be a little more welcoming to newcomers with its opening hours, but get through the initial confusion and you'll find a charming RPG that boasts an enjoyable battle system. Meanwhile, a solid supporting cast prop up a middling story, and some great dungeon crawling moments will keep you coming back for more. Despite several unnecessarily daft design choices, jumping into the shoes of Kirito can be a lot of fun, and for the game's budget price, it's easy to recommend to anyone who's up for a spot of anime adventure.