Strata Editor

Strata is as much a modding tool as it is a mod in it's own right. Strata makes non visable values that lay in minecraft exposed and editable without the need for scripting or creating entirely new mods to do so. 

Want to update the HP value of a mob? Strata can do that.
Want to modfify spawning behavior of an ore? Strata can do that. 
Want to disable blocks, items, or even crafting recipes? Strata can do all that and more.