Right so i use ableton and the program does not use buses it uses groups but you can not not have groups in groups-still with me?
You can route a Group to a new audio track in Ableton, and use that new track as a group for any tracks/Groups you send there. You can even send that newly created group onto another empty audio track, and make a further group, and keep repeating if you so wished.
All you need to do is create a track, call it 'All Drums Group' or whatever, then go to the mixer channel for the tracks you want to send to the 'All Drums Group' track, and select 'audio to' as 'All Drums Group' for the tracks you want to go to that group.
Also, set the channel 'Monitor' setting for each re-routed track to 'off' because you will be monitoring it from the new Group now. And on the 'All Drums Group', set the 'Monitor' to 'In' So that you can hear all the newly re-routed tracks.
It's easy to set up, and gets around ableton's group limitations.
PS: You need to have the In's/Out's box visible on the mixer tracks to do any routing, if it's not visible, then click on the I/O button (bottom right). If the button is yellow it's visible, if it's greyed out it's hidden.