As you may have already gathered, Aristocrat released their very popular 50 Lions slot game online in August of 2011 at the game Account group casino, MoneyGaming. The same site also has the 'More Chilli' slot and the original 'Queen of the Nile' slot, in addition to 50 Dragons and I'm hoping at some point the 100 Lions variation, although right now it's sadly not on the development schedule at Aristocrat.
Or at least, Aristocrat haven't announced any plans to follow up 50 Lions with 100 Lions but as slotjunkies will be aware, the roster of Aristocrat online slots has been growing at a reasonably regular rate. To be totally honest, the 100 line version is more popular with Asian gamblers - I saw a lot of those slot machines in Macau alongside the banks of 100 Dragons which were even more prolific - and with online gaming illegal in most of Asia, perhaps that's why there is no rush by Aristocrat to release it in the online world.
Both games are pretty much the same of course so you aren’t really missing out - all you are really doing with 100 Lions is dabbling with bet sizes to increase the chances of winning but you could just double the bet on a 50 Lions game! But it does look pretty when you get the big win with all that extra symbolism available! For now at least, you will have to be content with 50 Lions in the online environment.