heavy cavalry engaging heavy cavalry

[Nathan Ross]

I remember reading that he equipped his horse with iron-tipped clubs to beat the opposing cataphracti. I can't remember what battle this was though.

This was at the battle of Turin, with Constantine opposing Maxentius's clibanarii. It isn't clear whether the club-armed troops are cavalry or infantry though - Panegyric IV of Nazarius implies that Constantine was leading his own 'mailed cavalry' and opened ranks to draw the enemy in, but isn't clear about the identity of the clubmen!