You know, there's something I can't really grok in the TTRPG community, and it's the desire for a, how do I put it, "Paint by numbers" sort of adventure. A game where everything goes right, at the exact time its supposed to, with the players only ever making an impact via backstory. No desperate struggle, no clever ideas or unexpected turns, never using the sword of doom to punch through the dread citadel's walls, only using it for its +3 bonus to strike enemies. I just don't see the appeal, because to me, that's just what video games are!
Novice GMs are bad at improvisation and don't know to prep effectively, hence the railroady nature of the games they run. If you have a GM like that, buy a copy of "The lazy DM" by Mike O'Shea for them.
This is why I run Paranoia. There's no danger of anything going according plan in that game. Things will go wrong and they will go wrong catastrophically.
I mean, it is nice some times to have a linear plot. But it is also nice to have player's creativity give you ideas on what to do. Or shit being on fire, that's what dice are for.
1- If the item is currently in the game, then it's the DM that have put them there in the first place. It's fine to take them away if you made a mistake, but it's your mistake, better own to it.
2- This is hilarious as I just gave my players a blank check where they can get any item whatsoever. Only one. But I'm waiting with excitement on what they will end up with.
lvl 2 player at the lvl 15 end-game citadel: I attempt to break down the walls of the impenetrable fortress with the Sword of Doom
"A bright flash emanates from the place of contact as the two unbreakable items collide. It expands into a small explosion in an instant, letting out a deafening noise. When your eyes clear from the flash, ears still ringing, a small, 2 foot deep crater is broken out of the 5 foot thick unbreakable wall. Half the sword is vaporized from the heat of the impact, and the powerful runes are destroyed. The shockwave hits your character in a rush of heat and force. Roll a Dex save (or a little force damage).
Many people far and wide heard the impact. A dragon is rising in the distance from the tower of the dark mages... Wanna run?"
Dude I once put the Fighter into a vegetative state because of an intelligence level of -1.
He tanked all the magic damage with his shield of weaving, but not the effects.