I felt this was needed scince were supposed to be experts. My favourite combo with Lucas is using pk freeze on the enemy then land a fully charged smash up on them. The combo causes about 40% damage and will usually kill them - It generally doesn't work when they are over 70% damage or people who have annoyingly quick fingers. Another good combo to try is using upB with Mr game and watch to send them up and then press downA to smack them into the ground. If it works (which it probably will.)they will suffer about 30% damage altogether in 3 hits.
Mine is a Diddy combo. You first do a dash attack followed by an up smash. Then you jump into the air and do your uair. After this, you put a banana on the ground and then jump up to dair them onto the banana.
This next death combo will only work on noobs and is really cheap (but deadly for you if you fuck up). As toon link, you go to the edge and camp there. When your opponent comes over, you use your hookshot grab and throw them off the edge. Then, you use your dair when they try to recover thus meteoring them to their doom! lol (that's so cheap)