 This actually started out at explaining to someone how the title card mappings are edited, but it slowly drifted off into explaining all mappings, so I thought i&#39;d post it here.<br><br>EDITING THE TITLE CARD MAPPINGS:<br><br>You&#39;ll need to make a VRAM dump in DebuGens, move the dump to the Lost Library folder, and write the following commands:<br><br>ROM_PALETTE *Sonic 2 rom name*.bin 0x279A<br><br>IMPORT_PATTERN *vram dump name*.bin<br><br>LOAD_MAPPINGS_S2 *Sonic 2 rom name*.bin 0x147BA<br><br>That should load up everything you need to be able to edit the title card mappings. You can get DebuGens from the utilities archive on <a href='http://hacking-cult.org' target='_blank'>Hacking Cult</a>. To make a dump, go to:<br><br>CPU &gt; DUMPING &gt; GENESIS &gt; GRAPHICS &gt; DUMP VIDEO RAM<br><br>Make sure you do this when the title card is fully loaded. You can specify where to save the Vram dumps to in the options.<br><br>          ------------------------------------------------------------------------------------------------------------------------<br>Only standard object mappings can be edited using Lost Library. Any level art or static art must be edited using hex, and will follow a certain format. The Sonic and Tails objects also cannot be edited in Lost library, due to the way their art is dynamically loaded when needed. The format for the title screen itself, and all the other menus is as simple as this:<br><br>1. Dump the VRAM, and open it in Tile Layer Pro.<br><br>2. Decompress the menu art mappings you want to edit, and open them up in a hex editor.<br><br>3. Each word (2 bytes, 4 nybbles) represents 1 tile. The number specified in this word is the tile number in the VDP dump. For example, if you wanted the 3rd, 8th, and 11th tile in that order horizontally, this would be written as:<br><br>0003 0008 000B<br><br>Remeber that the values are in hex, so the 11th would be the 11th hex value, which is B. Only the last 3 nybbles are used for the tile ID. The first nybble is used for specifying the palette line and whether the tile is flipped. I&#39;ll write more on this another time, so for now just try experimenting with it. Just remember that 64 words (that&#39;s 128 bytes) is equal to 1 horizontal screen width. After that, the mappings will wrap down vertically by 8 pixels, and carry on on this line, underneath the other line. For the calculations, just remember this:<br><br>ASPECT RATIO = 320 x 224<br>TILE = 8x8<br><br>Therefore:<br><br>320/8 = 64<br>224/8 = 44<br><br>This means that 64 words is equal to a screen width, and 44 vertical lines is equal to a screen height. In total, your title screen mapping file should be 1A90:<br><br>64 x 44 = 1A90<br><br>I think that&#39;s how mine ended up anyway, or something around that. Of course, all these calculations were made in hex. Just remember to compress your mappings file again before inserting into the rom and you&#39;re ready to go.<br><br>          ------------------------------------------------------------------------------------------------------------------------<br>The Sonic/Tails mappings format isn&#39;t much different from the normal objects format, but you have to work with a couple of other things as well.<br><br>First of all, you must remember that Sonic&#39;s art is always dynamically loaded to the same place in VDP in each frame. Due to this, you can&#39;t just simply specify a certain tile for each fragment  and leave it as that like you do with normal objetcs.<br><br>The common format for objects is as follows:<br><br>NNNN -  ( YY - SS - FF - TT - <b>FF</b> - <b>TT</b> - XXXX )<br><br>NNNN is equal to the number of fragments that make up the sprite. This is specified ONCE per sprite. After that, the part in brackets is repeated the number of times specified by NNNN.<br><br>YY is the position of the fragment on the Y axis.<br>SS is the size of the fragment (refer to end of post)<br>FF controls the mirroring/flipping of a sprite (refer to end of post)<br>TT refers to the VRAM tile to be read<br><b>FF</b> is the same as FF, but is used by 2P mode.<br><b>TT</b> is the same as TT, but is used by 2P mode.<br>XXXX is the position of the fragment on the X axis.<br><br>This part is common to all objects. However, the Sonic/Tails objects need something else editing to make them work, which ties in with these mappings. This bit is slightly more complicated, and is used for dynamically updating the VDP with the character art. The format is:<br><br>NNNN - ( ST - TT )<br><br>NNNN is the number of times the bracketed section is repeated.<br><br>S specifies the number of 8x8s to be loaded to VDP from the character art.<br><br>TTT specifies the starting tile from which this art will be loaded.<br><br>You need to write this data to make the VDP update with the correct art. Once you have done this, you can edit the mappings properly for the characters, and make the mappings relate to the loaded art. They are different in this sense, coz with normal objects, the tiles of the art are always in the same place, whereas with the character objects, they are replaced.<br><br>          ------------------------------------------------------------------------------------------------------------------------<br>Now for the reference tables:<br><br>SIZE OF FRAGMENT TABLE:<br><br>Format of table = Hex value -- Height (in tiles) -- Width (in tiles)<br><br><!--c1--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>CODE</b> </td></tr><tr><td id='CODE'><!--ec1-->00 -- 1 -- 1 &nbsp; &nbsp; &nbsp; &nbsp; 01 -- 2 -- 1<br>02 -- 3 -- 1 &nbsp; &nbsp; &nbsp; &nbsp; 03 -- 4 -- 1<br>04 -- 1 -- 2 &nbsp; &nbsp; &nbsp; &nbsp; 05 -- 2 -- 2<br>06 -- 3 -- 2 &nbsp; &nbsp; &nbsp; &nbsp; 07 -- 4 -- 2<br>08 -- 1 -- 3 &nbsp; &nbsp; &nbsp; &nbsp; 09 -- 2 -- 3<br>0A -- 3 -- 3 &nbsp; &nbsp; &nbsp; &nbsp; 0B -- 4 -- 3<br>0C -- 1 -- 4 &nbsp; &nbsp; &nbsp; &nbsp; 0D -- 2 -- 4<br>0E -- 3 -- 4 &nbsp; &nbsp; &nbsp; &nbsp; 0F -- 4 -- 4<!--c2--></td></tr></table><div class='postcolor'><!--ec2--><br><br>FORMAT FOR FLIPPING/MIRRORING:<br><br>+08 - Flips Horizontally<br>+10 - Flips Vertically<br>+20 - Palette line 1<br>+40 - Palette line 2<br>+60 - Palette line 3<br>+80 - Sprite always in foreground<br><br>They have a + sign because you can add these together to produce multiple effects at once. Just add up and use the corresponding result.<br><br>That&#39;s basically about it. Any questions, ask.<br><br>*Credit to Hivebrain for the format layouts* 