  Abell 3266 is a massive and complex merging galaxy cluster that exhibits
significant substructure. We present new, highly sensitive radio continuum
observations of Abell 3266 performed with the Australian Square Kilometre Array
Pathfinder (0.8$-$1.1 GHz) and the Australia Telescope Compact Array (1.1$-$3.1
GHz). These deep observations provide new insights into recently-reported
diffuse non-thermal phenomena associated with the intracluster medium,
including a 'wrong-way' relic, a fossil plasma source, and an as-yet
unclassified central diffuse ridge, which we reveal comprises the brightest
part of a large-scale radio halo detected here for the first time. The
'wrong-way' relic is highly atypical of its kind: it exhibits many classical
signatures of a shock-related radio relic, while at the same time exhibiting
strong spectral steepening. While radio relics are generally consistent with a
quasi-stationary shock scenario, the 'wrong-way' relic is not. We study the
spectral properties of the fossil plasma source; it exhibits an ultra-steep and
highly curved radio spectrum, indicating an extremely aged electron population.
The larger-scale radio halo fills much of the cluster centre, and presents a
strong connection between the thermal and non-thermal components of the
intracluster medium, along with evidence of substructure. Whether the central
diffuse ridge is simply a brighter component of the halo, or a mini-halo,
remains an open question. Finally, we study the morphological and spectral
properties of the multiple complex radio galaxies in this cluster in
unprecedented detail, tracing their evolutionary history.
