Lifetime it will probably be RDR2 > CoD > Ass Creed > BF. It wouldn't surprise me if CoD beat RDR though.
More to the OP though, which suffers the most because of the crowded month...... there will be no way for us to know. But, I think BF is probably at the highest risk of being lost in the hype around the others. Ass Creed probably has some risk as well. CoD doesn't have any risk, as it is always the biggest release of the year. Nobody is going to miss it. RDR is so highly anticipated that nobody is going to overlook it.
All of this assumes that RDR hits the stated release date. I think there's a 50% chance that it is pushed later into the fall. If that's the case, then there's probably enough hype to be had by every release in October.








