While the series has its roots on Japanese computers and there have even been entries on the SNES, PlayStation and PlayStation 2, Thunder Force has always felt like a Sega series – and as of 2016, that's officially the case as the company now owns the rights to all of Tecnosoft's back catalogue. It's perhaps unsurprising then that Sega has chosen what many people rank as the best 16-bit instalment to spearhead its new Sega Ages range on Switch (alongside Sonic the Hedgehog, it should be noted). What we have here is one of the finest 2D shooters of its era, perfectly emulated and accompanied by some welcome extras.

Thunder Force IV (horrendously retitled as Lightening Force: Quest for the Darkstar in North America) originally launched in 1992 and followed hot on the tail of the almost-as-beloved third entry. The series is famed for its stern difficultly, rocking soundtracks and polished presentation, and out of all of the 2D entries, this fourth game is arguably the zenith. You being the game with a choice – you can select the starting order of the opening four levels before moving onto the tougher final stages. Your ship is equipped with an adjustable rate of speed and picking up special icons during play grants access to a series of different weapons, which can be cycled through at will.

From the word go, Sega Ages Thunder Force IV is an intense experience, with enemies assaulting your position from all four cardinal directions, often with little in the way of warning. Unlike a lot of shooters which give you the opportunity to avoid incoming fire, Thunder Force IV subscribes to the 'memory' style of play; learning when things happen is key to survival in some of the harder sections of the game. Despite the sharp difficulty curve, Thunder Force IV is more forgiving than its forerunner thanks to the fact that levels are incredibly tall; you can fly about a screen's height in either direction, a mechanic which we imagine is designed to show off the utterly insane amount of parallax scrolling but also gives you much-needed breathing room.

While there are diehard Thunder Force fans out there who consider this episode to be a little on the easy side, M2 – which is in charge of these Sega Ages ports – clearly thinks otherwise, as it has included a 'Kids Mode' which permits you to retain all of your weapons upon death. If you've previously tried to enjoy Thunder Force IV and have struggled because taking a hit means losing your burgeoning arsenal, this new novice entry point might be the breakthrough you need. Despite the rather patronising title, Kids Mode arguably makes the whole experience more palatable, especially for those coming in completely cold to the franchise.

Then there are the features which will presumably become common across all Sega Ages titles, such as save states, customisable controls, screen filters and interchangeable boarders. Thunder Force IV also packs in an online ranking mode which allows you to download and view replay data recorded by other players – a neat touch which allows you to pick up some tips from the best Rynex pilots in the world (or Styx, as you can unlock the ship from Thunder Force III as well).

That's where the bonus features end, however – which is disappointing, despite the authentic level of emulation achieved by M2 here. It would have been nice to see a few more new modes to keep you coming back after the credits roll, and while it's not the Switch's fault, we miss the amazing 3D effect that M2 incorporated into the Japan-only release of Thunder Force III, which shipped on Sega 3D Fukkoku Archives 3: Final Stage. We get the impression that we'll grow to miss autostereoscopic 3D effects more and more as time goes on.

Conclusion

While the debate about which Thunder Force entry is the best ever rages on through the decades, there can be no denying that this fourth title – the final one to launch on the Mega Drive – is one of the best shooters of the period and absolutely stands up today, despite the passage of time. The visuals are detailed and eye-catching, while the vertical scrolling still looks impressive by modern standards. It's a shame that more new content couldn't have been added, but if you're looking for the ultimate way to relive this classic blaster, then this is your best option – even better than the original cartridge, thanks to the inclusion of that surprisingly addictive online ranking mode.