The only way to pull this off, is to use multiple cyclers and toggle their visibility, once needed.
To make the table fall over - you should make 3 cycler_sprites. First with the idle animation, second with the falling over animation and the third one with the idle fallen over animation.
Now you place all 3 in one place, you make the 2nd and the 3rd table cyclers invisible (Render mode to Solid or Texture and FX ammount to 0), and you keep the 1st one visible. Now you'll have to encease the table with an invisible func_button (clip it, to make it match the table).
The button's properties:
Target: table_fall_mm
Health if shootable: Depends on how many shots you want fired at the table, to make it fall over. I'd use something like 25.
Now once you use or shoot the button for 25 hp - it triggers the fall over multi_manager.
To make the fall look realistic - you'll have to trigger 4 env_renders, to hide/show the animations of the falling table.
1st - hides the idle cycler (table_idle)
2nd - shows the falling table cycler (table_fall)
3rd - hides the falling table cycler (table_fall)
4th - shows the idle fallen over sprite (table_fallen)
You will also need some ambient_generics for the table fall sound, to make it all more realistic.
The multi_manager properties:
render1 0
render2 0
fall_sound 0
render3 <the length of the falling animation>
render4 <the length of the falling animation>
Now there will be only one problem - the bounding button. It would look really stupid, if the fallen over table had the same boundings, as the 1st table, wouldn't it? Luckily - func_buttons have the same properties, as func_doors. Accordingly to the table height - you'll have to make the button go down, to match the height of the fallen over table. You'll just have to make sure, that the 'Don't move' flag
is not ticked.
And that's it. To make it reset next round - you'll have to make a multi_manager, named 'game_playerspawn' and trigger 3 more env_renders, to hide the 2nd and the 3rd table cyclers, and show the 1st idle table cycler.
It's a pretty complex entity setup, although it should work pretty good with proper timing.
I'd make an example map, but I don't have HL atm.