the only altcoin that's actually worth a shit is monero, it's effectively the only coin used on darkmarkets ( so the only REAL crypto currency ) and the only one that still carries the lable "privacy coin", the devs are serious about privacy and know what they're doing https://www.getmonero.org/
you can easily buy monero with *any* payment method at https://localmonero.co
you don't have to go thru some scam exchange
99.9% of crypto are scams and while blockchain might have useful applications ( like a scoreboard or a tasklist on a collective project ) "currency" is the least likely scenario. Most crypto currencies function like derivatives or credit default swaps: speculative financial assets, except there is nothing 'real' holding them up at all their value is completely a projection of future value: imaginary. There will one day soon come a great crash that whipes 90% of altcoins off the map.
Full Disclosure: yes a hold some monero, yes, i want to drive up the price of monero so i can buy more drugs with it, It's fucking great. Buying drugs on deep web is the only good thing to come out of the crypto shitstorm.
* the only other coin i might consider is $oxen which is related to lokinet https://oxen.io/