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Even better if the foe was already almost dead. When you slap something for huge numbers it's also fun having the DM describe the wreckage that's left of your opponents.
I feel like some Table Top games are more prone to this than others, just based off watching some different IP's being played.
My first casting of Time Stop went overboard like this. I rolled 5 turns, and those 5 Delayed Blast Fireballs did enough structural damage to the cavern we were in to give us just enough time to confirm that everything on that end of the cavern was destroyed, before the cleric plane shifted us out of there. Lich and minions down? ✅ Lich's phylactery destroyed? ✅ All other magic items and treasure destroyed? ✅ Whoops. Apparently doing almost 500 damage instantly causes cavern collapses, and blows up magic items, furthering the damage.
I've never played a TTRPG where I got to play around with 9th level spells or the equivalent and now I'm jealous. That's insane!
We got to 40th level in that campaign. I played an Epic Wizard/ Epic Dweomersmith. The magic items I made for that character, and the rest of the group probably were technically minor artifacts. For instance, my headband was +6 to Str, Con, Wis, Dex, and Cha, +36 to Int, +100 to concentration, spell craft, knowledge arcana, and knowledge religion.
By the end of the campaign we had exterminated all the mind flayers and aboleth in several prime materials, as well as the astral plane of existence. Never could get permission to kill the ones in Sigil or the City of Brass