I've been trying to keep arcade conversions out of my Top Tens where possible... after all, there are so many great original games for these systems that it almost seems a waste to include something that was copied from something that was, despite the best efforts of the programmers, better. But some arcade conversions were such amazing programs that they deserve to be remembered in their own right. R-Type on the Spectrum was one such game.
Everybody knows R-Type. You're the pilot of the legendary R-9 fighter, battling the evil Bydo empire over numerous levels. You can pick up an add-on for your ship, called The Force. You must use this strategically to get through the levels, whether as a shield or extra firepower. Colourful extra weapons can be collected to give you an edge against the enemy.
I was never a massive fan of R-Type in the arcades. It was like the game version of The Timewarp to me... you had to do all the right moves at all the right times or you died. I'm not very good at dancing, and I've not very good at following patterns in games... I like to fly by the seat of my pants. There were lots of scrolling shoot 'em ups in the arcades that I preferred to R-Type.
That being the case, I probably shouldn't include R-Type in this list. However, it's such a miraculous achievement that I feel I have no choice. For everything to move as well as it does, with as much colour as there is... it's an amazing piece of programming. You can't help but be impressed, and you're compelled to keep playing to see if the standard is maintained throughout the whole game.
It is, and Spectrum owners were all the better for it.