Supercharged creepers created by the Flim Flam enchant can destroy terrain sometimes if they are killed with the use of a Lava Bucket, or a Thaumcraft Fire focus.

How to recreate - Hit a friend with Flim Flam until Supercharged Creepers spawn, and then kill the creepers by placing down Lava.

Can't reproduce with just OpenBlocks. This (and every other similar report) is probably interaction with other mods. Closing, since there is no bug in OB code.

Creeper spawning can be disabled by setting following config value:

S:flimFlamBlacklist <
    "creepers"
     >