5 Latter-Day Magic Items Converted to OSE

 Here's five magic items from later editions of D&D converted to rules-light, old school presentations. I've used Old School Essentials as a base, since it's the current lingua franca for much of the OSR.

Thanks to spearsandspreadsheets for giving me some ideas for what to convert!

Dwarven Plate

Sources: 3.5 Dungeon Master's Guide

This massive suit of plate mail is made of adamantine (found in meteorites), impregnable against any attack.
Weight Weighs 1,000 coins.

Protective Qualities The wearer reduces the damage dealt by any physical attacks against them (weapons, monsters, or traps) by 3.

Resistant Highly resistant to any damaging effects and saves as a level 12 dwarf.

Unenchanted Special because of its materials and is unenchanted by default. A spellcaster may be able to enchant it using magical research.

Immovable Rod

Sources: 3.5 Dungeon Master's Guide (note: there's already an OSE version of the immovable rod in the Advanced Treasure book, but this is a bit closer to the original)

This rod is a flat length of iron with a button on one end.

Anchoring: Pressing the button causes the rod to anchor itself to its current position in space. Once anchored, it can only be moved by a wish or other godly magic. (Even gravity does not affect the anchored rod.) An anchored rod can support up to 80,000 coins of weight.

Releasing: Pressing the button again releases the rod.

Ladder: Two or more immovable rods can be used in concert as a ladder unaffected by gravity.

No Charges: Does not use charges, may be used an unlimited number of times.

Ring of Climbing

Sources: 3.5 Dungeon Master's Guide

Grants supernatural climbing abilities.

Climbing: The wearer can climb on most surfaces automatically. They have a 1-in-4 chance of climbing a sheer or slippery wall or other vertical surface. If the roll is failed, the wielder falls at the halfway point, taking falling damage as appropriate.

Ring of the Ram

Sources: 2e Dungeon Master's Guide, Baldur's Gate II

Grants the power to attack enemies or objects with telekinetic force that looks like the head of a ram.

Attacking Enemies

Usage: A target within 30' may be attacked for 1d10 damage.

Resisting: The target may save versus spells to resist being knocked down or pushed away 30'. Circumstantial modifiers may apply (target is unusually stable, unusually strong, or larger than human-sized).

Attacking Objects

Usage: An object within 30' may be smashed open, with a 5-in-6 chance of being broken. Magically locked or held doors or portals can be broken open by this effect.

Resisting: Magical or enchanted objects may save versus spells to resist being broken.

Usage frequency: The ring may be used up to once a day.

Screaming Bolt

Sources: 3.5 Dungeon Master's Guide

A crossbow bolt that screams as it flies, causing fear.

Number Found: 1d4 screaming bolts are found at a time.

Enchantment: +2 bonus to attack and damage rolls when used.

Screaming The bolt screams through the air as it is fired. All enemies of the wielder within 20' of the bolt's arc of fire must save versus spells or be struck with fear and spend their next turn fleeing from the wielder at maximum speed.

Rest, Healing and Hit Points

This is a set of healing and rest house rules I came up with for the Swords and Wizardry Forgotten Realms campaign I'm running. They should be usable for any retroclone or relative of D&D from Basic through to 2e AD&D; design notes are at the bottom.

They speed up healing hit points (and only hit points), as my game uses a Death and Dismemberment table with a fair amount of grievous wound results that lead to actual convalescence. The rules also add more detail to resting, including inn room quality, camp preparations, and so on.

Feel free to use these, hack them, and adapt them for your own game. If you do use them, I'd love to hear how they work for you!

These rules replace the standard natural healing rules. These rules only handle recovering lost hit points, not recovering from grievous wounds, diseases, or other such conditions.
A creature that can naturally heal from injury (ie: not undead or a construct), heals hit point
damage as long as it rests for an extended period. By default, this is eight hours of sleep, for
humans and many other such creatures. Depending upon a creature's abilities, the duration
and nature of this rest may differ: elves dream in the reverie instead of sleeping; thri-kreen do
not sleep or dream but must still rest. This period of rest can be interrupted (such as by
nighttime attacks) to a limited degree, but severe or prolonged interruptions or poor
conditions may prevent any healing from occurring. Rest for healing's sake can only be
accomplished once every 24 hours, unless a special effect allows otherwise.
The basic rate for such healing is the formula (X+Constitution bonus) x HD = hp healed per rest.
X as a value represents the quality of rest, and is 1 by default unless modified. (Most modifiers
to rest affect the value of X.) X can never be reduced below 1 and can never exceed 5. A
creature's constitution bonus is the bonus for having a high Constitution score which is added
to hit points per Hit Die. (If a creature would have a Constitution penalty, treat it as 0 for the
purposes of resting.) Every creature has Hit Dice; only whole Hit Dice count for the formula. (ie:
A monster with 4+1 HD has 4 HD for this formula.)
The default values for the formula which apply to many creatures are (1+0) x 1 = 1 hp healed
per rest. This includes low-level monsters, most NPCs, and first-level PCs. (Exceptions do apply,
of course.)
Resting In Communities
Resting in a community can increase the value of X, depending upon the quality of
accommodations used. In general, accommodations (including inns, boarding houses, and cost
of living expenses during extended downtime) are rated 1 to 5 for quality. The
accommodation's quality is the value for X when resting in that accommodation. (Example: a
first-level character with no constitution bonus is resting in a rating 3 quality inn room. Their hp
healing rate is (3+0) x 1 = 3 hp healed per rest.) Higher quality accommodations are usually
more expensive, or require some other basis (such as a well-outfitted stronghold.)
Even if a creature is resting on the streets, X would remain 1. (Yes, this does mean there's not
really much benefit gained from the absolute worst common room resting spot.) Sleeping
rough does possibly risk guards pushing the sleeper to move, pickpockets, and other such
calamities, possibly severely interrupting rest and allowing for no healing. Paying for
accommodation reduces the risk of any such interruptions to nil, unless danger is already
established in some way. (ie: assassins in the night, Psycho-style accommodations, sudden
cataclysmic events.) In other words, paying for or establishing accommodation guarantees safe
sleep without the random encounter tables coming into play. (And now the worst common
room resting spot has a use again!)
If a creature is resting for a tenday in the same community and has had no severe interruptions
to rest or other taxing activities during that time (combat, extreme exertion, etc), they regain all
of their hit points at the end of the tenth rest.
Resting In Dangerous Areas
Equipment, skills, and preparation by adventurers can increase the value of X.
Especially good food eaten during rest (premium rations, exotic treats, a well-cooked meal)
increases X by 1. Any source of food may only provide one bonus per rest in this way: for
example, a character could eat a well-cooked stew of freshly caught deer and then share a
bottle of elvish wine with their comrades, providing two separate +1 bonuses to X.
Especially luxurious equipment (a premium bedroll, finely-made tent or similar) can also
increase X by 1. Any single piece of equipment can only provide one bonus per rest, and only
for the people directly using it to rest. (Only one character can sleep on a premium bedroll, but
multiples could share a large exceptionally-well made tent.)
Engaging in acts of camaraderie and morale can also increase X by 1. (A bard might tell stories,
the party could play dice or cards before going to rest, et cetera.) This bonus can only be
gained once per rest.
Poor environmental conditions can reduce X if not properly handled. Freezing in cold weather
or sweltering in hot weather without proper preparation would reduce X by 1, as an example.
Extremely poor conditions (such as severe dehydration) may count as severe interruptions,
preventing effective rest at all! The GM will inform the PCs of any such conditions that apply
and give them an opportunity to resolve them as part of making camp as appropriate.
Resting in dangerous areas always risks interruption and random encounters. Unless resting is
persistently interrupted (a foe using guerilla tactics or a particularly unlucky night), rest is not
prevented by interruptions during the rest period. In general, a party resting in dangerous
areas should expect that between making camp, resting, any interruptions, and beginning-of-adventuring-day preparations (including tearing down camp), the party has actually been
resting for twelve hours or three "watches" as a rule of thumb. (Most actions in D&D, S&W, and
similar games that are described as taking an entire "day" actually describe an eight hour long
period similar to the North American workday, so twelve hours at rest does not prevent
traveling, exploring, or day-long activities from other sources.)
If a party wishes to reduce their chances of being interrupted in dangerous areas, they may rest
clandestinely, without lighting a fire. This reduces X by 1 by default, prevents engaging in acts
of camaraderie to increase X, and other bonuses may not be available (such as preparing a
well-cooked meal.) However, resting clandestinely generally halves the chances of random
encounters while resting (depending upon the location and possible encounters, the exact
amount may differ.)
Special Note: There are many spells and magical effects, from rope trick to Mordenkainen's
magnificent mansion that help make resting in dangerous areas safer or more pleasant. These
effects are adjudicated on an effect-by-effect basis. Particularly strong effects may allow
creatures to rest like they are in a community.
NPCs Resting
NPCs have access to the same tools as PCs, depending upon their level, wealth, and other
resources. NPCs usually do not have a Constitution bonus to hp, and the quality of their home
determines their rest quality in their communities. NPCs are unlikely to have special
preparations for bonuses to X while resting in dangerous areas, but will act to resolve poor
environmental conditions.
Monsters Resting
Monsters are extremely unlikely to have access to any bonuses to X while resting in dangerous
areas, and monsters never have Constitution bonuses to HP. Monsters are immune to any
environmental conditions in their native environments/habitats or other areas they are resistant
to. For example, a fire elemental can rest safely in a volcano, even though it is not their native
habitat and would count as a severe interruption for most creatures. However, a monster does
count as resting in a community if it's in its lair or a similarly safe space, and may receive a
bonus to X for high quality accommodations. (This is dependent upon the monster. A dragon
resting on its massive hoard of coins has no soft bed nor royal meal, but certainly counts as
sleeping in quality 5 accommodations.)
Design Notes
This system makes healing hit points, and specifically hit points, much easier than the default in
many old-school editions of D&D, clones, and relatives. It assumes that you have other systems
in place to promote downtime, including downtime spent resting or healing. (Diseases,
poisons, or severe injuries from critical effect or death and dismemberment tables are common
examples.) Healing hit points this quickly makes them clearly luck/grit/exertion in the narrative,
instead of direct meat points. This system does not work for all games or all narratives, and it's
not meant to.
Tenday is what the Forgotten Realms uses instead of weeks, a period of ten days of which there
are three to a month. If your world uses a different calendar, replace tendays with a significant
number of days in your world. If you don't have days or your timekeeping is wildly different, let
me know how you've hacked this! Similarly, accommodation quality going from 1 to 5 is taken
from the 2e Volo's Guide supplements for the Forgotten Realms; you may change this for your
own setting.
Sources
The Retired Adventurer's Into the Depths house rules:
https://retiredadventurer.blogspot.com/2017/04/into-depths-update.html
The Infinity Engine series of D&D computer games
Swords and Wizardry Complete Rulebook (SW)
Player's Handbook (2E AD&D)
These Dragonsfoot threads: https://www.dragonsfoot.org/forums/viewtopic.php?t=39957 &
https://www.dragonsfoot.org/forums/viewtopic.php?t=20240