There are a whole lot of matchups where your opponent has items to use against you. However, they can often be just as useful to use if you know what you're doing. These are a few strategies I've picked up that might help out when you come across the right situations.
Jump Cancelled Throws
Lucas has an awful glide toss. It hardly sends him anywhere. So there's really no reason to use it. Jump cancelling your throws will actually make Lucas slide further than you would be glide tossing. The input is simple enough, while running, press your jump button and then immediately Z or C-stick in the direction you wish to throw. This causes you to throw the item using your standing throw animation rather than your laggy running throw animation. In addition Lucas keeps some momentum so he'll keep sliding in the direction you're going. With correct spacing, hitting with this can ensure a free Fsmash (especially with Diddy's Bananas.) Jump cancelled throws are IMO the most important item technique to know with Lucas.
Zap Jump Throw
A little known fact is that you can zap jump by throwing an item. The input is simply pressing the jump button and then the throw button immediately after on your second jump. Lucas will do the super jump and throw the item on the way up. While this is not necesarily the most useful thing you can do with an item all the time, it can every once in a while help you out. Imagine you're being edgeguarded with items for instance Link's bombs or Peach's turnips. You catch an item, you use it to recover, you laugh as your opponent screams "WTF?" Situational at best but good to know for when you can use it.
Picking Up Items
There are some more efficient ways of picking up items than others. You really need to keep these in mind especially when picking up items that can hurt you such as bananas or ROB's gyros.
Running Pick Up
One of the worst things you can do is to pick an item up with Lucas's dash attack. That move is lag city. The safest way to avoid this is to allow Lucas to skid before picking up an item. Dash toward an item and as you begin to approach, let go of the analog and press A as you approach it. It may take some time to get used to the spacing so that the item doesn't hurt you. If you do this correctly it has the least lag of anyway to pick up an item. Simply running and grabbing an item without the dash attack even has more lag than this.
Aerial Pick Up
Okay so technically Bair is the best choice to pick up items in the air with. Because oddly enough it has the least aerial lag on the end meaning you could do another attack after it earlier than with any other aerial. This seems really odd but you can test it by doing a full hop aerial immediately and then follow as fast as you can with a Fair. You'll notice Bair to Fair, the Fair comes out slightly higher than any of the other aerials. Go figure, the aerial with the slowest startup has the least lag on the end. Another reason is because it autocancels near the begining of the move as well as the end meaning if you're near the ground when you catch an item in the air, you will not land with lag most often. However, it's really not that big of a deal. I find it's easier for me to just use a Nair to grab items because mentally it's simpler. Lucas grabs an item in the air when you input the aerial and since Bair takes a little while to come out it's kind of disorienting to time whereas Nair comes out almost immediately. Just a matter of preference and situation really.
Falling Pick Up
Picking up an item on the ground as you're falling from the air toward it. The best way to do this is with Uair. Uair autocancels on the ground and the hitbox pretty much protects you should you mess up. This way you don't have to deal with accidently doing a Nair early and having to deal with the lag or something. This is a great way to pick up bananas.
Item Strategies
May be updated if further ideas are brought up
Diddy Kong
Use those bananas against him! If you have a chance to, run up and grab a banana to chuck at him. Using a jump cancelled throw you might even score yourself a free Fsmash. Just don't get too caught up in it. Remember your goal is to kill Diddy, not banana spam. Also remember that if you bat a banana ONLY WHILE IT'S IN THE AIR, it becomes yours, meaning Diddy will trip on it while you won't. Sadly you rarely get a chance to do this but if you can it's absolutely amazing for mindgames.
ROB
That gyro can be a b*tch. He will spam it. It's fairly easy to run up to it and grab it while it's still spinning if you just learn the spacing for it. This could take some practice to get used to. But you really don't want him to be able to use it. If you can hit him with it go for it by all means. Another great strategy against the gyro is to bat it while it's spinning. This causes it to become yours meaning if ROB touches it while it's spinning it hurts him while it won't hurt you. This can be great for messing with his head and keeping him away from one of his most annoying projectiles.
Zero Suit Samus
Those powersuit parts can really hurt. They give ZSS an annoying way to rack up damage as well as an approach at the beginning of every match. Against ZSS I like to start just jabbing because many times they will immediately start throwing parts. If you're jabbing you will always either block or catch whatever she throws. Once you get a hold of some parts, use them to your advantage. A good hit with one will knock her really far. If you're lucky enough to get her on the edge, she is completely screwed. Throw a powersuit part down at the ground near the edge. This will cause it to bounce dealing knockback if ZSS stays on the edge too long or gets up at any point. You can get beginning of the match kills this way sooo easily if they aren't expecting it. Just try really hard not to get hit by those things. Batting them back is always a nice option as well.
Wario
Don't break the bike. He needs the bike to recover so if he's dumb enough to leave it on the stage just leave it alone. You'll gimp his recovery a lot by not destroying it and force him to eat it when he has the chance meaning possibly not getting edgeguarded. The bike parts are pretty weak. Don't get preoccupied trying to use them.
Jump Cancelled Throws
Lucas has an awful glide toss. It hardly sends him anywhere. So there's really no reason to use it. Jump cancelling your throws will actually make Lucas slide further than you would be glide tossing. The input is simple enough, while running, press your jump button and then immediately Z or C-stick in the direction you wish to throw. This causes you to throw the item using your standing throw animation rather than your laggy running throw animation. In addition Lucas keeps some momentum so he'll keep sliding in the direction you're going. With correct spacing, hitting with this can ensure a free Fsmash (especially with Diddy's Bananas.) Jump cancelled throws are IMO the most important item technique to know with Lucas.
Zap Jump Throw
A little known fact is that you can zap jump by throwing an item. The input is simply pressing the jump button and then the throw button immediately after on your second jump. Lucas will do the super jump and throw the item on the way up. While this is not necesarily the most useful thing you can do with an item all the time, it can every once in a while help you out. Imagine you're being edgeguarded with items for instance Link's bombs or Peach's turnips. You catch an item, you use it to recover, you laugh as your opponent screams "WTF?" Situational at best but good to know for when you can use it.
Picking Up Items
There are some more efficient ways of picking up items than others. You really need to keep these in mind especially when picking up items that can hurt you such as bananas or ROB's gyros.
Running Pick Up
One of the worst things you can do is to pick an item up with Lucas's dash attack. That move is lag city. The safest way to avoid this is to allow Lucas to skid before picking up an item. Dash toward an item and as you begin to approach, let go of the analog and press A as you approach it. It may take some time to get used to the spacing so that the item doesn't hurt you. If you do this correctly it has the least lag of anyway to pick up an item. Simply running and grabbing an item without the dash attack even has more lag than this.
Aerial Pick Up
Okay so technically Bair is the best choice to pick up items in the air with. Because oddly enough it has the least aerial lag on the end meaning you could do another attack after it earlier than with any other aerial. This seems really odd but you can test it by doing a full hop aerial immediately and then follow as fast as you can with a Fair. You'll notice Bair to Fair, the Fair comes out slightly higher than any of the other aerials. Go figure, the aerial with the slowest startup has the least lag on the end. Another reason is because it autocancels near the begining of the move as well as the end meaning if you're near the ground when you catch an item in the air, you will not land with lag most often. However, it's really not that big of a deal. I find it's easier for me to just use a Nair to grab items because mentally it's simpler. Lucas grabs an item in the air when you input the aerial and since Bair takes a little while to come out it's kind of disorienting to time whereas Nair comes out almost immediately. Just a matter of preference and situation really.
Falling Pick Up
Picking up an item on the ground as you're falling from the air toward it. The best way to do this is with Uair. Uair autocancels on the ground and the hitbox pretty much protects you should you mess up. This way you don't have to deal with accidently doing a Nair early and having to deal with the lag or something. This is a great way to pick up bananas.
Item Strategies
May be updated if further ideas are brought up
Diddy Kong
Use those bananas against him! If you have a chance to, run up and grab a banana to chuck at him. Using a jump cancelled throw you might even score yourself a free Fsmash. Just don't get too caught up in it. Remember your goal is to kill Diddy, not banana spam. Also remember that if you bat a banana ONLY WHILE IT'S IN THE AIR, it becomes yours, meaning Diddy will trip on it while you won't. Sadly you rarely get a chance to do this but if you can it's absolutely amazing for mindgames.
ROB
That gyro can be a b*tch. He will spam it. It's fairly easy to run up to it and grab it while it's still spinning if you just learn the spacing for it. This could take some practice to get used to. But you really don't want him to be able to use it. If you can hit him with it go for it by all means. Another great strategy against the gyro is to bat it while it's spinning. This causes it to become yours meaning if ROB touches it while it's spinning it hurts him while it won't hurt you. This can be great for messing with his head and keeping him away from one of his most annoying projectiles.
Zero Suit Samus
Those powersuit parts can really hurt. They give ZSS an annoying way to rack up damage as well as an approach at the beginning of every match. Against ZSS I like to start just jabbing because many times they will immediately start throwing parts. If you're jabbing you will always either block or catch whatever she throws. Once you get a hold of some parts, use them to your advantage. A good hit with one will knock her really far. If you're lucky enough to get her on the edge, she is completely screwed. Throw a powersuit part down at the ground near the edge. This will cause it to bounce dealing knockback if ZSS stays on the edge too long or gets up at any point. You can get beginning of the match kills this way sooo easily if they aren't expecting it. Just try really hard not to get hit by those things. Batting them back is always a nice option as well.
Wario
Don't break the bike. He needs the bike to recover so if he's dumb enough to leave it on the stage just leave it alone. You'll gimp his recovery a lot by not destroying it and force him to eat it when he has the chance meaning possibly not getting edgeguarded. The bike parts are pretty weak. Don't get preoccupied trying to use them.
