Mod talk:Obsidian Mod/@comment-50.45.65.160-20120712183827/@comment-89.136.25.72-20120922152206

Well, I just got the same error too, so here's what you'll have to do to fix that:

1. Go to My Documents/My Games/Terraria/ModPacks/Obsidian Mod/NPC.

2. Locate the file Dark Wyvern Body 2.cs and open it with a text editor (i use Notepad++).

3. Use the find option to find the word "byte" (ctrl+F and type in byte, press Enter). It will only return one result (lucky us).

4. Replace the word "byte" with "ushort", save and close the file.

5. You might have to do the same for the next files:

Dark Wyvern Body 3.cs

Dark Wyvern Body.cs

Dark Wyvern Head.cs

Dark Wyvern Legs.cs

Dark Wyvern Tail.cs

Snake Body.cs

Snake Head.cs

Snake Tail.cs

WormBody.cs

WormHead.cs

WormTail.cs