Waaaaaaay too complicated!I thought of this, Being owned by C4's quite often. Disguise-able C4's Upgrade.
Price, I have no actual pricing idea, Although it should be high.
./upgrade c4
Your C4 has been upgraded, Use /c4disguise (block)
Alright, So I could go /c4disguise cyan, Every c4 I place, They have to be Cyan. (This would mean Lightning would be un-use-able un till changed) I could then think, 'Hm, It's getting too obvious' /c4disguise cobblestone.
<3
And c4s are mostly used by _Aperson155_ and Kevind_123, so you can better mark them so you know where you NOT should be! ;D