By staking your MPH, you are eligible to collect 88mph protocol's revenues distributed as MPH and voting rights.
A 20% fee on the fixed-rate interest, which is computed at the time of deposit/topup, but stays in the pool until the deposit is partially/fully withdrawn (if it's a partial withdrawal only the fee on the withdrawn part is taken out of the pool)
A 0.5% fee on the deposited amount when an early withdrawal happens. This fee is taken out of the pool when the withdrawal happens.
The liquidity incentive tokens received from protocols the fixed-rate APY pool deposits into (e.g. Compound, Aave). This never enters/exists the pool, it is sent directly to the dumper contract which will sell the tokens into MPH on the market every 14 days (bi-weekly buyback); think stock dividends without dilution.
When your MPH is staked, you receive xMPH in return for voting rights.
xMPH is a fully composable token, continuously compounding. When you unstake you will receive all the originally deposited MPH and any additional from protocol revenues.
You can unstake at any time without penalty.