Haejin,
Great question!!
That is the beauty of the DGTX exchange.
Adam Todd the CEO has solved this issue with Automated Market Makers.
200 Million DGTX Tokens have been allocated to the Automated Market Makers (AMM).
The AMMs are programmed to break even, so in times of high voliatilty the AMMs will still step in and provide liquidity as they always do, because they will not be afraid of losing money or the fast moving markets.
That is 20% of the entire DGTX supply dedicated to providing liquidity, which is especially important when BTC and ETH are flying up or down.
So even in times of high volatility where Bitmex fails and doesn't let you trade because; the order book drys up, and the Bid and Ask Spreads are $50-$100 apart (I've seen this), the Digitex exchange will still be able to provide good liquidity and tight bids and offers!
RE: Digitex Futures Exchange (DGTX) The $0.00 Commission Revolution