Bitmex

Bitmex is currently the largest Bitcoin exchange according to BTC volume. You can short bitcoin or go long with their top-of-the-line margin trading system. Coins available for trading on Bitmex are: Bitcoin, Cardano, Bitcoin Cash, EOS Token, Ethereum, Litecoin, and Ripple. Deposits are only available with BTC.

Bitmex has a quality referral system and a VERY informative blog.

Notes:
No USA citizens allowed, although KYC is very minimal.

Update 8/14/2020:
KYC is coming to Bitmex https://blog.bitmex.com/announcing-the-bitmex-user-verification-programme/

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