If you're one of the elite who can make it past wave one in Defender. Sirius might just have the thing for you. It's called Repton and is probably the best Defender game I have played on the Apple.
In fact, not only is it a good version of the arcade original, it also has a mini version of Scramble thrown in for good measure. It's fast and furious, and has the meanest bunch of nasties Sirius has ever thrown at you.
Alongside the dreaded Nova Cruisers, the fearsome Quarriors and the fightful Single-ships are a whole host of other invaders, all dedicated to your destruction. Piloting your Armageddon ship, you cruise over a scrolling landscape of buildings which represent your home planet Repton. Blocks are ripped off the buildings by the aliens and taken to build their own surface base. Your ultimate aim is to stop them completing this, but survival comes first.
The Armageddon ship "released from Sirius Base in view of this dire situation" has a limited supply of "nuke bombs" and an energy shield, as well as the usual laser gun. Releasing a nuke bomb will send anything on the screen into oblivion (bar you, naturally!). Switching on the shield renders the ship untouchable, and uncontrollable!
Aside from attacking you and building the base, the invaders are keen on stealing energy from the planet. If allowed to, they will use the energy to build their base - not good news for you.
Should they complete the base, the game explodes into a frenzy of sound and animation as the ship's failsafe mechanism takes over.
Automatically an Armageddon bomb is detonated which destroys everything on the planet (apart from you-know-who), and the alien base falls below ground.
Now it's your mission to fly underground to the alien's main generator. On the way, rockets are fired at you and ships peel off from the roof to dive into an attack. Make it past these, and the generator appears. Just one carefully-placed shot, and you've blown up their entire base. Then for wave two!
Repton has all the usual CTRL functions for restarting the game and so on, plus an option to change the joystick axes. To help you in your mission, there is a radar display at the bottom of the screen, as in Defender, and a speed indicator. There's also an iron-on T-shirt transfer so all your friends can tell you've got the game.
If you like hot arcade action with good graphics and sound (and who doesn't?) you'll enjoy Repton. Admittedly I'm a terrible Defender player, but I think Repton is a challenge worthy of any arcader.