I have a License Key for Reign of Chaos and Frozen Throne. Can I still download and play this, or are we forced to buy Reforged?
You’ll be set with this link. If you want to update to the latest patch, you’ll get the Reforged treatment, though you ought not to need to purchase it if you’ve linked those license keys to your Battlenet account.
If you wanna stay Pre-Reforged, you gotta stop the game from updating by blocking the game executable from accessing the internet. Or you gotta use custom servers like Unforged.
With a RoC key linked to your Battlenet account, you can play the Classic mode (includes RoC and TfT) within Reforged without any additional purchase.
You can use the links above to install the legacy clients, but there’s no Battlenet functionality.
As Leviathan has posted, your RoC CD Key can still be used to play Warcraft III using the Reforged client, but with classic graphics only (reforged “HD” graphics locked out). You can even play with other players who are using Reforged graphics in the same game, although some custom maps are limited to Reforged players only (sadly…).
TFT CD key is no longer used as far as I am aware. RoC is enough to get access to both RoC and TFT content as they were merged together in the run up to Reforged.
Only if you use Reforged. If you download classic TFT you still need it.