"Everytime I tried to append it doesn't work, atleast not with the MM8editor, ....."
This is a common 'feature' of that editor. It occurs quite often when trying to change/import/edit '.dlv' and '.blv' entries in GAMES.LOD. The 'fix' is both simple and sometimes quite complicated.

I'll do a quick change of the size 'stat' of the Goblin, start a new game tonight and see if it makes any difference. If it does, I'll put together a quick .PDF, picture-oriented 'tutorial' on what to look for using a Hex Editor for changes like this. I assume that you already know how to 'export' the '.bin' file and have a basic understanding of "Hex" (0 --> F) entries.

Events.lod, dsft.bin, offset 0x2A controls the scale, or display size or each sprite. To make the goblin “Titan-size”, **all** 21 sprite sets (set 859 thru set 879), **all** ‘.m246xx’ entries (which is the sprite index for the Goblin) must be set to “5”.

Now this is an all-or-nothing deal. Once you do it, every encounter on all maps/dungeons will have Titan-sized Goblins. There is a way around this all-or-nothing, though. Generate an 'alias' set of the sprites, re-index them, and ....

I'm sure you can figure out the rest of the process.