Equipping Dual Cylinders in the 2nd Equipment slots means sacrificing potential for another skill set.
And now I'm thinking of Guard Cylinder + Lance in one, with Shylien Magic Knuckles in the other.
Now Giants got pretty much everything covered (except Puppetry).
Dat versatility.
Jack of all trades, master of none.
Except in this case, you're losing out on a lot for "versatility".
You also miss out on the best 2 talents, best 3 if you count guns.
Using overkill as an example doesn't really help your case.
If an enemy is a bit away you could just Water Cannon instead of moving to smash it.
Easy access to Shock is also there.
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Although we're all bickering over things we have little to no information about, we'll have to wait and see how it goes.
Except 30k isn't overkill and Water cannon is underkill. It's a bad skill that does bad damage unless you overspecialize in it. So in this example, all you'd do is push it back and not kill it.