Evolution-of-combat. It's this retarded (my opinion) system they've instated that's completely changed the game. You can like dual-wield weapons, monsters have weaknesses, shit like that. Someone else can probably go more into detail about it
EoC means Evolution of Combat as Video stated before, people are using now "EoC" word and "Oldschool" or "2007/07RS" to call normal runescape and oldschool version of this game. EoC is available at runescape.com , oldschool is available at oldschool.runescape.com , basicly oldschool RuneScape is same thing as EoC, but before introduction of this combat update.
Oldschool is now nearly as cool as it was in 2007, with unique combat system and without bitching about microtransactions.
I hope my post helped you abit, maybe it's confusing but well, I'm tired
If you've got any more questions feel free to PM me
Maybe it's abit silly, but yeah this video describes EoC
[YOUTUBE]Rmmom7jwz6M[/YOUTUBE]
It's the new and improved version of combat that doesn't include one click and then monging out at your screen. You can do combinations of things to make kills quicker, it's a change for the better.