In endless void fissure missions, you get a bonus reward every time you open a relic. At least that's what people have told me. I'm not sure if this is true for the following two reasons:
1) The wiki about this subject reads:
Should you collect the necessary Reactant per interval and open your Relic, a bonus will occur and you will be allowed to re-select a new Relic for the next interval.
This sounds like you only get the bonus if you choose to stay and play another round (or interval).
2) After the fifth interval, you supposedly get a void relic. However, this relic doesn't show up in the mission rewards like the other relics you've obtained do.
So when do we really get these rewards? Do we get the first booster after round 1 or after round 2? Do we get the first relic after round 5 or after round 6?