..err. gaara had the tailed best within him back then so it's hard to say how powerful he truly is without it, but even then controlling crocodile is iffy at best. at the end of the day gaara is a flesh and bone guy that can be hurt, and crocodile is capable of harming him with himself not being damaged at all
Gaara's feats are insane. He could probably solo a majority of the One Piece-verse, honestly.
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"The Daemon lied with every breath. It could not help itself but to deceive and dismay, to riddle and ruin. The more we conversed, the closer I drew to one singularly ineluctable fact: I would gain no wisdom here."
I mean, I agree Gaara has better sand feats, and now that he has sealing, a way to win too, but only a few people look at this thread, and it's hardly going to be considered definitive on a large scale.
I don't see how sealing Crocodile in sand is supposed to beat him. He is sand. He could just seep through one of the walls or floor, or just blow it up.
Croc could probably turn himself back since he's turned rock into sand before. Plus I doubt he would actually let Gaara do that to him, not lying down anyway.
The sand will be dense and it would be hard for him to maneuver through it and gaara is controlling the sand and would not ever let that happen. Gaara would have more control over the sand. And the sealing tag will just stop him from moving or thinking period.
No crocodile would not even be able to hit gaara with his hook and gaara can just control him. Crocodile is not beating gaara.
He did not have many speed feat from his fight with luffy as he mostly just stood there and took the hits and survived only cuz he is a logia. And croc was not winning against any big names in the war he just happened to get around.
That's just by crushing rock with sand, he can't do the reverse. Though as you say, he can make really dense sand.
Density isn't the primary factor here, though.
Sealing as in putting a magic seal on it.
It works on someone who creates liquid that melts the sand away allowing him to travel through even Gaara's dense sand easily. Once the seal's on, the person is immobilized and can't take actions.
More good points on gaara's part people need to face the fact that gaara>crocodile. Gaara would never be beat by a villain who was beat by pre g2 luffy. Though crocodile could probably beat alot of strong characters still.
As we see in the case of Raikage and Whatshisface, the seals can be stopped and torn off before they even take effect. Crocodile can easily do this by just separating the sand with the seal on it from himself, just as Mr No-brows did. Or he can easily phase through the walls as its being placed or as Gaara is forming the pyramid, even if you don't think he can do so after the seal is in place.
And the guy didn't turn into liquid, he just used it to break up the sand. Crocodile can literally turn into sand and escape through the walls or floor themselves.