That's strange, since the old mod did it. Go download it and see for yourself.
Ok let me clear things up.
At some point between v13 and v21, Badspot added a feature to the game to not add a collision box to bricks with other bricks. This was after the creeper mod went out of fashon. (?) What this meant was that bricks placed in other bricks were no longer detectable by containerBoxSearches.
You'll notice if you try to run the old mod and get creeper to grow through a brick, it will - and then it will keep growing through the brick. In the exact same spot. Until your game nearly crashes from looking at it. Until recently, this version also did that. This means that a lot of older creeper maps that use this mechanic no longer wo-
Wait.
I've literally just remembered I already wrote a two-paragraph post about this. Why am I doing it again? Read the first one:
Okay so the mod had this really wierd bug where it couldn't detect creeper bricks that had grown through non-raycasted bricks anymore. This meant it kept trying to grow through the bricks in question CONSTANTLY - within 10 minutes there are like 20 1x1s clogging up my 2x2 vent cover, all placed in the same area because engine changes since v15 mean the creeper can't detect it's own bricks anymore if they're placed on top of others. This also makes it impossible to eradicate the creeper properly because the last brick can't be hit by any sort of projectile or raycast.
The only way to fix this problem is use $Typemasks::FxDTSBrickAlwaysObjectType instead of $Typemasks::FxDTSBrickObjectType. This means creeper can't grow through non-raycasted bricks anymore but it couldn't anyway because of the above bug. So some old creeper maps (Anybody's Factory, Awasp's Sewer etc.) will have to be redone in some areas to work with the new version. Sorry about that.
Anyway, back to mapping. I realize I've probably announced the server too early, so I'm locking this for now.