Cap'n Kobold
Hero
For my tastes they should have just made this a "normal" or "default" encounter.
:mostly rhetorical: What's the point of combat if it's not deadly? Why bother with encounters that are there just for XP boosters or to fit the "minimum # of encounters per day". It's fine in OD&D where you can roll through 6 -8 encounters in an hour of play in your 70s style dungeon of 100 rooms. It's a poor fit for any modern versions of the game.
"Normal" or "Deadly are just labels the system uses. A "medium" encounter close to the end of the adventuring day, when the everyone is out of hid dice and the casters are down to cantrips is more lethal than a "deadly" encounter at the beginning of the day that could just be novaed through.The closest and most recent example might be the Witcher - He carries two swords: Steel for fighting people, and Silver for fighting monsters (which are often less resistant/more vulnerable to silver in the fiction.)Also, of note... is there ANY fiction out there with a hero with a golf-bag of magic swords with different property like you were apparently supposed to have as 1e-2e Fighter? Was that a thing before DnD? Yes, there is stories where you need to find the ONE legendary weapon to defeat the bad guy, but those stories don't end up with the hero then going to collect the legendary weapon from OTHER stories. They have ONE and that's it.