I suggested this a few time in the past but it was not very well thought out and simply just "please add it" type of thing. This time, I'll try to propose it properly. Where did I get the idea I got the idea from looking at some other games that use DLCs as a form of adding more content and that have a scenario editor with an option to share created scenarios (mainly looking at Arma 3 and DCS world). Prettymuch all of these games allow use of DLC content by an AI even if the player don't have it. In other words, you can play and make scenarios where an AI uses DLC content without having to own that DLC. Why does it matter I'm probably getting a bit ahead of things but it matters quite a lot when making and downloading workshop scenarios. Those who haven't played TSxx may not understand me but cases where you can't play a scenario because you don't have a train that is used as an AI are quite common. In that case, you surely don't want to buy a train just so that an AI can drive it especially if it's something that you might not want to drive. If we had free AI trains, only DLCs required to play a scenario would be the route and the player's train. It also matters a lot for those who like making scenarios (like me). Using a lot of AI train results in me having to put a lot of DLCs as required which means that very few people can actually play the scenario. Another option is to only use rolling stock that is shipped with the route which then results in AI traffic looking very repetetive. Having free AI trains could solve this issue. Having free AI trains is also one of the steps towards multiplayer. What are the advantages - better variety of AI trains in scenarios (both workshop and official) - better variety of AI trains in service mode beyond what can be done with substitution (NEC trains on LIRR etc.) - free stuff at no extra cost (AI trains are also content. Or aren't they?) What are the disadvantages - slightly larger game size How should it work Everything that is required to make a train work as an AI (models, textures, sounds) should be bundled in the base game but everything that is required for a player to drive it (complex physics, systems logic) should be separate and downloaded just like now. If a player tries to play a scenario that starts in the driver seat of a DLC train that he don't have, the game should stop loading, return to main menu, and throw a message saying "You need a DLC XY to play this scenario". If a player tries to take over a DLC train that he don't have (in service mode or in a scenario), the game should not let him take it over and throw a message saying "You need a DLC XY to take over this service". There should be an option to disable substitution to "not owned" trains in service mode.
