A Bitcoin miner with sufficient mining power can adopt a selfish mining strategy to increase their relative revenue. Studies have shown that the time-averaged profit of a selfish miner begins to increase when the mining difficulty adjusts in favor of the attacker. Due to the delay in difficulty adjustment, it takes some time for this attack to become definitively profitable. The first part of the presentation introduces a new variant of the selfish mining attack, called "smart intermittent selfish mining," aimed at reducing the initial period of losses associated with selfish mining.

The second part of the presentation explores the relationship between selfish mining profitability and Bitcoin's difficulty adjustment mechanism (DAM). It is often thought that incorporating orphan blocks into the DAM could make selfish mining completely unprofitable. This hypothesis is challenged by the presentation of the "orphan exclusion attack," a strategy allowing the attacker to prevent honest miners from reporting orphan blocks. This attack demonstrates that even when orphan blocks are taken into account in the DAM, selfish mining can remain profitable.

The third part of the presentation addresses the fact that most analyses of selfish mining assume a fixed block reward. However, in the near future, a more volatile block reward is expected, as the protocol reward decreases with halving events, with transaction fees becoming the main source of block revenue. Consequently, due to this transition to a more volatile reward environment, selfish mining could become profitable from the launch of the attack, even before any difficulty adjustment.