What’s up with all these attacks against FTC? Was it because there was someone who was big into a competing coin, or was it just for fun?
There are a few things quoted as “Attacks”. There have not been times when it is proved there is a deliberate attack, i.e. someone has paid or has enough power to try to double spend.
This resulted in the first major update to Feathercoin to implement Automatic Check pointing or ACP. Once this happened and there was a “double spend issue”, FTC would reject that chain - i.e. It becomes an Orphan chain.
However, Feathercoin still abides by the normal rules and the longest chain wins. So there are 2 competing chains untill the attacker error chain gives up or the normal chain becomes longer.
There similar reasons Bitcoin has also suffered longer orphan chains than originally specified, but FTC does suffer a couple of long chains early on.
There is another known “attack”, it turned out to be someone testing, one was an attempt to flood the network with dust payments, was noticed later but had no detrimental effect.
I designed eHRC initially as a potential replacement for ACP but in the end it was used to reduce the effect of coin switching. It does make it harder for someone to achieve network dominance for long enough to do anything. So we don’t tend to get the long orphan chains.