They were clearly going the Samurai route with one combo giving you haste and the other giving you a damage buff. Thing is the buttons light up arbitrarily and your combo will always end correctly as long as you press one of the two glowing buttons. That's not intuitive at all.

There is oversimplification and button bloat. Viper is leaning towards the former. Having two single target buttons and two aoe buttons that went through their 1-2-3 and ending with Death Rattle/Last Lash would have been the best way to go.