You encounter the Githyanki leader Voss in Act 1, and if you follow his questline through to completion, he'll give Lae'zel a legendary sword in Act 3. Kostov agrees that this is the best sword for melee Githyanki builds, so obviously players figured out a way to get it in Act 1 by casting the Heat Metal spell, which makes characters drop metal weapons, on Voss. The problem is, the dialog initially tied to this sword could spoil events of Act 3. This forced Larian to adjust Lae'zel's lines knowing full well it would be enabling wildly overpowered early builds.
"The easy thing would be to block players from using Heat Metal on Voss," Kostov explains. "But we don't like that at Larian. We love this sort of stuff so let's fully support it. Let players keep the cool weapon. They found a way to exploit the game, let them have it, it's awesome. And rewrite Laezel's dialog to make sure it works in Act 1. This might mean recording new lines, it might mean hiding some of the lines, but supporting the player's creativity is awesome. We found out later
there's actually a wiki page for this exploit. It's super long too. That's awesome."