Milo: Enchanting and Runes
What this page helps you decide: which piece of equipment a rune should go into, which is decided by the published slot potency rather than by preference.
Milo works inside the Enchant building, positioned to Quill's left, and he handles three services that the sources list together: enchanting equipment, fusing runes and unenchanting equipment. He is the entry point to the whole rune system, which is the part of this game with the clearest published numbers and the most misunderstood ones. The single most useful figure he is attached to is slot potency: the same rune performs at 100% in a weapon, 60% in armour and 40% in a helmet. That one line decides most rune placement questions, and it appears on the official wiki and nowhere on any competing guide site.
Why slot potency is the most valuable number here
Most decisions about runes look like preference questions until you see the potency figures. A Corrode rune raising all damage the target takes is strong, but at 40% in a helmet it is doing less than half the work it would do in a weapon. Combine that with two other published facts - rune procs have no internal cooldown so they trigger purely on attack speed, and Corrode does not stack but refreshes duration - and the layout falls out mechanically. Your weapon attacks most often and carries the highest potency, so it wants the rune whose uptime matters most. Armour and helmet slots, at 60% and 40%, are where duplicate stacking effects like Burn and Methysis earn their place, since each additional rune of the same type sustains another stack.
The four runes in one paragraph
Corrode increases all damage the target takes from every source, does not stack, and refreshes its duration when reapplied; its short cooldown gives near-constant uptime, so carrying several is still recommended. Burn and Methysis are damage over time with identical mechanics, one stack per rune, strong early and noticeably weaker later. Frost slows the target and detonates for burst damage when the slow ends, and it benefits from Corrode's amplification, which is why endgame players pair them. Two independent community articles add a practical warning that the official page does not: do not run Frost and Burn together, because the fire effect removes the freeze before its damage lands.
What is not published about Milo's services
The cost of enchanting is not published. The cost or mechanics of fusion are not published - only that he does it. Whether unenchanting returns the rune intact, damaged or at a reduced level is not published. There is one adjacent item, the Rune Crack, recorded as obtainable through his enchanting area, with a Rune Cracker improvement noted in Update 11.1, and its exact function is undocumented as well. The Grocery does at least give a price floor for the runes themselves: level 3 Burn, Methysis, Corrode and Frost each sell for 3,000 Gold, which is the only rune-related price published anywhere.
Step-by-Step
- Put your strongest rune in a weapon. At 100% potency a weapon slot is worth more than two and a half helmet slots for the same rune.
- Follow the published endgame layout when you get there: Corrode on the weapon and helmet, with Frost or Burn on armour.
- Use Burn or Methysis early instead. The official guidance is that damage over time is a larger share of your total output at low levels, which makes those two better than Corrode before the endgame.
- Compare numbers before upgrading a rune. Upgrading rerolls every property - trigger chance, damage, duration and tick damage - and a higher level rune has a better possible range without any guarantee of beating a lucky low-level one.
- Fuse rather than discard duplicates, since fusing is one of Milo's three listed services, though no source publishes what fusion costs or produces.
- Use unenchanting when you replace a piece rather than losing the rune with the item. It is listed as a service, but its cost and whether the rune survives intact are not published.
Data Tables
| Slot | Potency | Best rune to put there |
|---|---|---|
| Weapon | 100% | Corrode at endgame; Burn or Methysis early |
| Armour | 60% | Frost or Burn at endgame |
| Helmet | 40% | A second Corrode at endgame |
Potency from the official Runes page, last edited 29 July 2026; placement from the same page's endgame recommendation. No competing guide site publishes these percentages.
Tips & Notes
- Milo is inside the Enchant building on Quill's left, which puts the sell menu and the enchant menu within a few steps of each other - useful when you are clearing inventory before a rune decision.
- Rune procs scale with attack speed rather than a timer, so a fast secondary weapon triggers more rune effects than a slow one carrying the same rune.
- Corrode is specifically flagged as worth considering from Tier 3 onward in the official Frozen Valley guidance, which is the transition point to change your layout.
FAQ
Where should I put my runes in Iron Soul: Dungeon?
Your best rune goes in a weapon, which runs at 100% potency against 60% for armour and 40% for a helmet. The official endgame layout is Corrode on the weapon and helmet with Frost or Burn on armour.
What does Milo do?
Three things: enchanting equipment, fusing runes and unenchanting equipment. He is inside the Enchant building, to Quill's left, and both sources that list the town's NPCs agree on the role.
Is a higher level rune always better?
No. Upgrading rerolls every property including trigger chance, damage, duration and tick damage. A higher level rune has a better possible range but the official guidance says to compare the actual numbers before swapping.
Sources
- Official Official Iron Soul Roblox Wiki - Runes — The 100/60/40 slot potency, all four rune mechanics, the reroll-on-upgrade rule and the endgame placement recommendation.
- Community Iron Soul Wiki (community) - NPC's — Milo's location inside the Enchant building to Quill's left, and his three services.
- Community Iron Soul Wiki (ironsoulwiki.com) - Items database — The Rune Crack obtained through the enchanting area, and the four rune types matching the official list.
- Official Official Iron Soul Roblox Wiki - Template:Shop — The 3,000 Gold price on level 3 runes, the only published rune price.