Look for new blockchains like NKN, Pchain, Seele, QuarkChain - they can be Etherium's killers and make x100 in near future, DYOR!
I think those who altcoins who claimed as eth's killer are already complete failure because they are just concepts that still needs proof. I would suggest Vechain, Wanchain and Utrust for a real x100 in few years.