ROM Hack I need help trying to open these .dat file

[Sonico2345]

Hello, Im new to these sort of things and was wondering if you could help me understand this .dat file. The file is called BObjMap.dat and its from Mario & Luigi 3. I believe this is a .obj file due to its name and was wondering how to open this file at all, cause if I change the extension to .obj it still won´t open. Maybe Im wrong abut the extension?

I saw in other threads that it was necesary to see the hex code of the file. Because its so big, Ill just put the beginning of it, since thats were the file signatures are, apparently.

Feel free to ask for more information if necessary, Ill do my best to answer them.
I apologize if this was asked previously. I havent found a specific answer because of the ambiguity of the dat files

4C 01 00 35 00 57 00 01 0C 00 1C 77 01 00 2C 01
00 24 5E 04 02 02 00 07 60 65 00 44 10 05 01 D7
04 00 03 04 01 00 69 20 2B 00 19 00 00 A5 C0 FF
08 04 10 06 29 40 1A 02 06 03 00 00 4C 01 00 35

 

[FAST6191]

Does not look like a file format I have seen before, and does not look to be compressed either (zipping it shaves several kilobytes from the main file). The repeating of 4C010035 at the start and end has me curious, though I looked at a bunch of other files (other than the sound file being the common sound_data.sdat file all the files appear to use .dat as an extension and have no particularly obvious markers) and they don't appear to share a start type or magic stamp or anything.

Edit.
Did find some ASCII in SMes_yo.dat
Only have basic tile viewers here but did not find much of interest in anything (tried obvious ones like font and UI in case it is one of those 3d games that appears 2d or something)

 

[Sonico2345]

Does not look like a file format I have seen before, and does not look to be compressed either (zipping it shaves several kilobytes from the main file). The repeating of 4C010035 at the start and end has me curious, though I looked at a bunch of other files (other than the sound file being the common sound_data.sdat file all the files appear to use .dat as an extension and have no particularly obvious markers) and they don't appear to share a start type or magic stamp or anything.

Edit.
Did find some ASCII in SMes_yo.dat
Only have basic tile viewers here but did not find much of interest in anything (tried obvious ones like font and UI in case it is one of those 3d games that appears 2d or something)

Since you mentioned it I've decided to see the hex again and noticed that this lines repeat themselves over and over up until offset 000007D2. Honestly Im not only amazed this flew over my head, but also that I only wrote the bare minimum for someone to notice it.

4C 01 00 35 00 57 00 01 0C 00 1C 77 01 00 2C 01
00 24 5E 04 02 02 00 07 60 65 00 44 10 05 01 D7
04 00 03 04 01 00 69 20 2B 00 19 00 00 A5 C0 FF
08 04 10 06 29 40 1A 02 06 03 00 00

(Btw im using the japanese version of the game because I wanted the files to be uncompressed from a beginning. I guess I was expecting to find the sprites in a silver platter, like it is in MK DS.)

The next lines of code after that repetition are as follow:

4C 01 00 38 00 57 00 01 0C 00 1C 77 01 00 2C 01
00 24 5E 04 02 02 00 07 60 65 00 44 10 05 01 D7
04 00 03 04 01 00 69 20 2B 00 19 00 00 69 40 08
05 10 06 C0 E9 FF 1A 01 16 01 00 00 00 00 00 00
38 00 2D 00 57 00 01 0C 00 1C 77 01 00 2C 01 00
24 5E 04 02 02 00 03 00 65 01 34 10 05 01 D7 04
00 01 04 01 00 D9 60 2B 00 60 00 00 35 F0 FF 02
00 00 00 00 44 02 00 70 00 55 01 02 0C 00 DD 1C
01 00 3C 01 00 79 2C 04 02 02 00 03 95 F0 01 74
10 05 9D 01 01 00 34 08 05 97 01 00 02 04 05 02
67 00 00 05 08 02 60 79 08 03 00 00 00 F8 A5 FF
60 15 00 08 01 9A 05 01 4B 00 60 0E 00 95 F0 FF
A0 18 01 A5 20 00 08 00 18 02 A5 E8 FF 1D 01 20
01 AA 2B 00 25 03 18 01 42 02 59 40 39 01 60 01
55 A0 01 C0 01 09 E0 61 01 00 00 00

Damnit, now im seeing patterns here as well, And after all this the hex changed once again, this time with much less zeros than the one above this comment. not gonna put it here tho cause at this point im tempted to put the whole hex code in here, so I should stop here.

Anyway, thank you for your help and assistance, I think you've helped me enough despite the elusiveness of the file nature. Have a nice day.