European competitions: Champions League, Europa League and Conference League

The European cup system was the hardest thing so far:

✅ Champions League: 32 clubs, group stage plus knockout
✅ Europa League: group stage plus knockout
✅ Conference League: for the smaller clubs

The notorious European cup bug:
Two legs, the away-goals rule, extra time, penalties. Over 100 prompts and three evenings went into this one. I nearly gave up.