Definitely litecoin, imo if btc fails at any time litecoin is going to replace it, it has as fast if not faster transactions, limited supply, segwit and it will implement lighting soon. Also holding ETC.
That's great. Litecoin does have the potential to rise up in the future but i dont think that it will replace bitcoin since bitcoin is the king of cryptos. Bitcoin will rule the cryptos until atleast the next 5 years, more i hope.