Usmash is hard to hit with. Here are a few ways that you can hit with Usmash or safely attempt to hit with Usmash.
1. Juggle Traps
Essentially what you're trying to do here is punish an airdodge or an aerial attack because (with very few exceptions) these won't allow the opponent to get through Usmash because of its monstrous hitbox and duration. Using Usmash in a juggle trap works best if you have already forced the opponent to waste their second jump (which often will allow them to escape.) Juggle traps are very hard to explain in terms that make sense unless you just try them out yourself. It's basically about knowing the range of your move in comparison to the opponent's mobility (in this case horizontal.) This will require some baiting and a lot of knowledge of how your opponent and his character play.
Note: Horizontal mobility is drastically decreased when an opponent fast falls. This is an easy hit if they make the mistake of doing it too close to you.
2. Spacing Errors
A less common way to hit with Usmash against good players is when you notice an obvious misspacing. Opponents who try to hit with aerials and miss because they don't know their hitboxes well are easy prey for Usmash. Also keep in mind that Lucas's hurtbox shrinks near the beginning of Usmash. You can use this to your advantage. Unofortunately, better players know their range better and won't fall into this.
3. Tech/roll Chasing
This is by far the most difficult way to hit with Usmash. You basically have to guess that they're going to roll toward you and predict it well enough ahead of time to have an Usmash waiting for them. This works best against predictable opponents after you knock them down with PK Fire or Fair or something. After some friendlies against Alpha Zealot's Diddy, I learned that Bannanas can be used to trick people into rolling into your Usmashes. In general this is a really risky way to try to hit with Usmash.
4. Ceilings
Ceilings make Usmash really easy to hit with because the duration lasts longer than invincibility frames on teching. So basically there's no way for them to get out of it. You may have to read their DI a little bit but not much. It's really handy. Works best on PS1 on the Windmill because they can actually get killed rather than bouncing up and down (like on Luigi's Mansion.)
5. Dthrow to Usmash
Still in testing. I've mostly done this against Marth but I've had it work on other characters as well. Dthrow and follow their DI with a running Usmash around 30-60%. They are forced to either jump or take the Usmash. If they jump they won't be able to get down in time to punish your lag.
6. Shield Poking
Usmash shield pokes. If you get into a situation where the opponent will give you enough time to Usmash and tries to shield it, you can hit them with it anyway if their shield is somewhat low. This is another pretty risky attempt.
7. Shield Pushing
If you're on a small platform or near a ledge, Usmash is safe against an opponent who is shielding. If they shield it, you can space it so that either you or your opponent will slide off the edge as it hits their shield making it so they can't punish. Since Usmash can't be spotdodged you can pull this off sometimes and get a safer chance at attempting to shield poke.
8. The Inescapable Brinstar Special
My own wonderous creation. It truly is a work of beauty when you can pull it off. The platforms of Brinstar are created perfectly for Lucas's Usmash. If you use Usmash from underneath either the left or right platform and the opponent is shielding with the right spacing, they cannot avoid getting hit. The one thing you have to space is that you have to make sure that the opponent is pushed by Usmash (if they shield) in the direction closest to the nearest edge. The reason this works is because if they hold their shield throughout Usmash, they will get shield pushed off the side of the small platform and the extended duration due to the stage will make them get hit by Usmash's still lingering invisible hitbox. If they roll, the platform is too small to roll out of range and they get hit by the lingering hitbox. If they spotdodge they get hit by the lingering hitbox. If they jump they get hit by the lingering hitbox. ****. The best way to set this up is if you see the opponent about to land on the platform ahead of time (often when they are recovering.) If you misspace it, it still may shieldpoke depending on the character and their shield damage.
As far as I know, no other stage allows this because the platforms are too big or there isn't any destructible terrain to extend the hitbox. I've done this multiple times to people and I only know of one character who can escape it and they've never done it against me.
9. Dtilt lock combo
After a Dtilt lock, wait a second and then walk forward and Usmash. They are forced to stand up and you get to kill them. Works great after Dair and it's flashier than Fsmash.
Usmash is a good move if you can hit with it. I've been working a lot lately on improving how often and safely I can hit people with it.
1. Juggle Traps
Essentially what you're trying to do here is punish an airdodge or an aerial attack because (with very few exceptions) these won't allow the opponent to get through Usmash because of its monstrous hitbox and duration. Using Usmash in a juggle trap works best if you have already forced the opponent to waste their second jump (which often will allow them to escape.) Juggle traps are very hard to explain in terms that make sense unless you just try them out yourself. It's basically about knowing the range of your move in comparison to the opponent's mobility (in this case horizontal.) This will require some baiting and a lot of knowledge of how your opponent and his character play.
Note: Horizontal mobility is drastically decreased when an opponent fast falls. This is an easy hit if they make the mistake of doing it too close to you.
2. Spacing Errors
A less common way to hit with Usmash against good players is when you notice an obvious misspacing. Opponents who try to hit with aerials and miss because they don't know their hitboxes well are easy prey for Usmash. Also keep in mind that Lucas's hurtbox shrinks near the beginning of Usmash. You can use this to your advantage. Unofortunately, better players know their range better and won't fall into this.
3. Tech/roll Chasing
This is by far the most difficult way to hit with Usmash. You basically have to guess that they're going to roll toward you and predict it well enough ahead of time to have an Usmash waiting for them. This works best against predictable opponents after you knock them down with PK Fire or Fair or something. After some friendlies against Alpha Zealot's Diddy, I learned that Bannanas can be used to trick people into rolling into your Usmashes. In general this is a really risky way to try to hit with Usmash.
4. Ceilings
Ceilings make Usmash really easy to hit with because the duration lasts longer than invincibility frames on teching. So basically there's no way for them to get out of it. You may have to read their DI a little bit but not much. It's really handy. Works best on PS1 on the Windmill because they can actually get killed rather than bouncing up and down (like on Luigi's Mansion.)
5. Dthrow to Usmash
Still in testing. I've mostly done this against Marth but I've had it work on other characters as well. Dthrow and follow their DI with a running Usmash around 30-60%. They are forced to either jump or take the Usmash. If they jump they won't be able to get down in time to punish your lag.
6. Shield Poking
Usmash shield pokes. If you get into a situation where the opponent will give you enough time to Usmash and tries to shield it, you can hit them with it anyway if their shield is somewhat low. This is another pretty risky attempt.
7. Shield Pushing
If you're on a small platform or near a ledge, Usmash is safe against an opponent who is shielding. If they shield it, you can space it so that either you or your opponent will slide off the edge as it hits their shield making it so they can't punish. Since Usmash can't be spotdodged you can pull this off sometimes and get a safer chance at attempting to shield poke.
8. The Inescapable Brinstar Special
My own wonderous creation. It truly is a work of beauty when you can pull it off. The platforms of Brinstar are created perfectly for Lucas's Usmash. If you use Usmash from underneath either the left or right platform and the opponent is shielding with the right spacing, they cannot avoid getting hit. The one thing you have to space is that you have to make sure that the opponent is pushed by Usmash (if they shield) in the direction closest to the nearest edge. The reason this works is because if they hold their shield throughout Usmash, they will get shield pushed off the side of the small platform and the extended duration due to the stage will make them get hit by Usmash's still lingering invisible hitbox. If they roll, the platform is too small to roll out of range and they get hit by the lingering hitbox. If they spotdodge they get hit by the lingering hitbox. If they jump they get hit by the lingering hitbox. ****. The best way to set this up is if you see the opponent about to land on the platform ahead of time (often when they are recovering.) If you misspace it, it still may shieldpoke depending on the character and their shield damage.
As far as I know, no other stage allows this because the platforms are too big or there isn't any destructible terrain to extend the hitbox. I've done this multiple times to people and I only know of one character who can escape it and they've never done it against me.
9. Dtilt lock combo
After a Dtilt lock, wait a second and then walk forward and Usmash. They are forced to stand up and you get to kill them. Works great after Dair and it's flashier than Fsmash.
Usmash is a good move if you can hit with it. I've been working a lot lately on improving how often and safely I can hit people with it.
