We do not allow any strategy that exploits the demo environment, guarantees profits with little risk, or that cannot be consistently replicated in real markets. The most common prohibited practices are: 

Latency arbitrage, reverse arbitrage, gap exploitation, or any abuse of platform or server errors/glitches;

Extremely fast trades taking advantage of atypical market liquidity that would be characterized as liquidity fraud, and/or microscalping (trades held for 30 seconds or less) in most trades;

All types of arbitrage (latency, statistical, hedge arbitrage, etc.);

Hedging between multiple accounts (own or third-party), including opposing positions on the same instrument or correlated instruments;

Group hedging, reverse trading, or any form of collusion between accounts;

Copy trading of external signals, copiers between different accounts, or use of "passing challenges" services; 

Account sharing or allowing someone else to trade on your behalf;

Martingale, aggressive grid systems, or "all-in"/gambling-style progressions;

Use of identical third-party trading EAs that generate duplicate trading patterns among many traders;

Exploiting news with bracketing (pending orders on both sides);

Any strategy that only works because it is being executed on a demo/simulated account.