1 button builds is a technical possibility, but they are usually inferior to builds using a button or two more
*and that’s ofc if we’re totally ignoring evade or movement rune which really should be a consideration to use too
Ex being you can make a retal warlord or regeneration warder using just 1 attack skill, but it will in all likelihood be “better”/more efficient if you add in ex ascension and or overguard on the warlord, or War Cry etc on the Warder
Doesn’t mean you can’t make the warlord not using vire’s might/blitz for movement or without ascension or overguard, just that in general/for most people it’s worth having those buttons
Like Medea even suggested, you could technically make a fully passive build if you wanted, although how fun it might be for you however might depend entirely on something else
you can make a build stupid tanky if you wish, requiring little to any input from the player, adding in “tolerable” dmg output might be a different matter tho
easiest way to make a low button build is pick a class with passive RR/no active debuff, 1 main dmg skill, and no temp buffs required (blood of dreeg/word of renewal to cover resists etc)
righteous fervor warlord or savagery warder could be one such