| SocratesOnFire |
I think Pizza Lord's interpretation is excessively conservative. The steadfast grapple is a magical grappling hook that does exactly one thing, it magically attaches to stuff. While we can agree that the item description is terrible (how did the this get past and editor?) I think it's pretty clear how the item was intended to work: when the grapple hits something, creature or object, it remains stuck to them until the listed conditions are met. If it's thrown at an object, it hits automatically. If it's thrown at a creature, it requires an attack roll (which really seems like it should be a touch attack, but eh).
The reason I don't accept Pizza Lord's interpretation is because of that third line: "Against creatures, the wielder must make attack rolls as normal." If the only effect of the grapple were to stick to objects and no part of it's magic had any affect on creatures, there would be no reason to additionally describe the means by which a creature may be struck with one. Lyre of Building doesn't have a line saying "attacks on creatures within 300' are unaffected" and Chime of Opening doesn't feel the need to specify that "creatures targeted by the chime are unaffected." The presence of that third line makes it clear that the item is expected to be thrown at and magically interact with creatures.
And even with Pizza Lord's interpretation, a character can still use it against a creature so long as that creature has equipment of some kind. The text does not specify that the object targeted must be unattended. I've played a fighter that used this grapnel on the end of a magically-treated adamantine chain to great effect, and I actually did target the opponent's armor to avoid having to make an attack roll.