Most of these games will have already ended up in your account at some point or other, but even if there's only one or two titles in the bundle that catch your fancy it's still worth the coffee-esque price of entry.
The entire package is selling for $4.27 right now (oh for the days when the AU$ was above parity). By my count, there's at least six games that should catch the attention of most PC gamers, but let's go through the whole list.
- Tropico 4: Steam Special Edition
- S.T.A.L.K.E.R.: Clear Sky
- Mount & Blade: With Fire & Sword
- System Shock 2
- To the Moon
- Prime World: Defenders
The weakest games out of this line-up are Deponia -- traditional point-and-click adventures have a limited audience and Daedalic's style can be very hit or miss -- and Prime World: Defenders, although I'd argue anyone who gets enjoyment out of tower defence games will actually find a lot to like about Prime World. It's been a few years since I fired it up, but it's more accomplished than you might suspect.
Magicka plays quite naturally on PC -- certainly more so than the console port -- although my experience with Arrowhead's mage slaughterhouse (because of all the friendly fire) was constantly beset with connection issues and bugs. It's undoubtedly in a much better state now, though.
The rest of the line-up doesn't really need defending. System Shock 2 is an unarguable classic and one of the few shooters from that era that manages to hold up well today visually (although some fan mods/patches go a long way to improving the experience on modern screens/systems). Tropico 4 is a competent city builder set around the theme of a loveable dictator -- well, my dictator is a loveable and benevolent leader at least -- and there's been plenty of fawning about To The Moon's story on forums and websites over the last few years.
Mount & Blade has enjoyed a consistent fan base on Steam for years for good reason, and the standalone expansion (With Fire & Sword) is perfectly fine if that's the time period you're looking to wage war in. Alternatively, if you have bugger all idea what the Mount & Blade series is about then Fire & Sword works as a useful introduction, and it's been quite the proving ground for modders.
S.T.A.L.K.E.R. Clear Sky is the sequel to the original survival FPS, and while it's generally considered the weakest of the Chernobyl-centred series the atmosphere and challenge should still have some value for horror enthusiasts.
You'll get a publisher-approved Steam key (for those wary about buying from third-party sites) for each of the games. It's not the only interesting package Bundle Stars has for offer right now, though. Their All Stars 5 Bundle has the same asking price as the package above and comes with Painkiller, Divekick and the 2013 reboot of Rise of the Triad, while a pack with all of the core Quake games and expansions is on sale right now for $14.54.