Tiberius' men swarmed what was left of Oliver's. Those good Patrick men that he was so proud of, now so uselessly placed. They that had entered into the storm so many times off the back of their General, and they who now found a storm so much bigger than themselves. A swirling quagmire in which no creature could escape from its sticky mud.
An effort of will. Not even truly Oliver's will. The horse beneath him, in Nelson, likely contributed as much to their disentanglement as anything that Oliver himself did. The men at the back of Oliver pushed him forward as well. There was a sense of buoyancy, like a chunk of wood rising back up out of the waters. The tides of battle carried Tiberius beyond Oliver, past him, along with the momentum of his charge, and Oliver too was forced to go the opposite way.