I think it means that he was the only Merganser about

Yet another deluded individual who don’t know what a Nazi nor a genocide is.

I know the feeling

I been told by someone that the magma chamber is connected to the nearby Erta Ale, Ethiopia’s most active volcano.

The Afar Depression is a volcanically active region which is part of the African Rift Valley.

And if not, the magma in the dyke intrusion could’ve mixed with a volume of underground water. That can also be a possible cause of the explosive eruption on a shield volcano.

Shield volcanoes usually produce effusive eruptions (more about the lava) but it’s unusual that explosive eruptions occur on them. What caused it? Well from my knowledge of volcanoes, my educated guess would be that a dyke intrusion mixed with older magmatic material.