I think you're trying too hard to sound epic.
While a shield could be cruel, no doubt, 'fell' is more often used of weapons than defences.
I doubt they're brimming with fish, so I'm not sure what you're going for. Was that supposed to be the AngloSaxon word for spear (as in gar-lic, spear leek)?
by "pelting-men" do you mean all ranged weapon wielders (i.e. including archers), or are you restricting that to e.g. slingers.
circling? spirals? odd choice of wording...
He's using a flexible fishing spear?
correct. But, wow that's obscure.
wouldn't happen with the fishing spear he's apparently using.
"shoals"?
But, aside from those minor quibbles, great update!
To answer these: a fell is actually an archaic English word for a pelt or a hide.
Yes, that is gar asin the old word for a spear.
Yes, pelting-men is meant to refer to all of the ranged-weapon bearers, and that's why I used that term in particular; there's only so many times you can refer to 'skirmishers' before you start seeing crosseyed.
Some of these you seem to have not quite understood the metaphor I was going for, and I can't really do much about that; for example shoal and gyre. There's been a consistent metaphor referring to the armies and to regiments of armed men with metaphors relating to the sea. See the first part in which Muwatalli's army is referred to as shoals, and banks, and waves rolling onto the plain.
Leister was supposed to be going with the theme mentioned above but, I think you're right, that one is too specific and I'll change it.
Liths is indeed an obscure word. But I like obscure words, and I don't really feel there's much harm in using the odd one now and again. It would be different if I was writing like Chaucer or Milton or even Edgar Allen Poe, but so long as it's only one or two I'm usually fairly comfortable. C.f gar, from above.