Draft:Scroll

Omega 0.90.4

Scrolls are single-use magical or informative items, shown as a yellow ?. Omega has 24 kinds, including blank paper, hint sheets and Jane's guide to treasure. Their strengths include choosing equipment, improving items and reaching places that ordinary movement cannot. Reading is slower than drinking a potion, and blindness or fear can prevent it altogether.

List of scrolls

All scrolls weigh 5. Values below are base values in Au, not guaranteed buying or selling prices. Item level affects random generation; it is not a character-level requirement. The brief effect column describes ordinary, non-cursed use unless stated otherwise; follow the item link for blessing strength, enchantment, failure and cancellation rules.

Scroll	Base value	Item level	Main use or limitation
Blank scroll	5	0	No magical effect
Hint sheet	10	0	One random hint
Identification	20	0	Identify one item; blessed, identify the whole inventory
Light	30	0	Light a qualifying dark room
Spells	250	1	Attempt to learn a random spell or reduce a known spell's mana cost
Teleportation	75	1	Same-level escape; blessed, choose a destination
Clairvoyance	25	1	Reveal terrain around a chosen point
Alertness	50	1	Improve searching and reactions to certain surprise attacks
Self-knowledge	10	1	Report character conditions and progress
Blessing	400	2	Raise an item's blessing, with dangerous curse-strength boundaries
Enchantment	200	2	Improve an item; already enchanted targets can explode
Displacement	50	2	Chance to evade monster melee hits
Jane's guide to treasure	50	2	Learn the identities of one random item category
Charging	100	2	Refill a stick, up to 99 charges
Law	100	2	Move alignment toward Law
True sight	50	2	See invisible creatures and overcome certain visual deceptions
Summoning	300	2	Summon a hostile random monster, even when blessed
The warp	100	3	Travel within the current dungeon, excluding its final level
Dispelling	250	3	Remove qualifying curses, monster abilities or magical terrain effects
Deflection	250	3	Deflect magical bolts; does not stop ball attacks
Cosmic flux	300	5	Rebuild the current dungeon level; hazardous different effect in town
Heroism	200	5	Temporary melee improvements
Acquirement	5000	7	Create an item; blessed, choose its exact kind
Wishing	10000	10	Choose from specific wish words; some choices are lethal

Obtaining scrolls

Scrolls occur in random treasure and monster loot. The pawn shop also generates stock at source level 5, making it a practical place to buy known scrolls. Its stock is finite, and neither the price nor availability is represented by the base-value column alone. High-level scrolls can appear in shallow loot, but are much less likely there; the complete table below gives the distribution within the scroll category.

Acquirement can produce any of the 24 kinds without the ordinary source-level filter. Bless it first to choose the exact scroll. The result normally starts uncursed, even though the acquirement scroll was blessed.

Ambrosias can turn certain corpses into blessed scrolls during daytime. A fnord yields summoning, a blipper teleportation, a phantasticon true sight, and either a murk fungus or a shadow spirit light. The price is twice the corpse's base value, with a minimum of 10 Au; the individual scroll pages give the relevant costs. These are transformation recipes, not promises that those creatures carry the scroll. Necromancers, separately, start with a scroll of spells.

Reading and identification

Use Peruse (r) with the scroll in accessible possessions. An item still in the pack must first be brought into an accessible slot. A normal reading takes 20 time ticks. Blindness and fear block reading before an item is consumed, so prepare a healing or fear-removing potion when either condition threatens an escape plan.

The selected scroll is normally consumed after its effect, including a failed or useless effect. Cancelling the initial choice of scroll consumes nothing; cancelling a later target is a different operation and generally still spends the scroll. In particular, cancelling an identification target still consumes its scroll despite suppressing that action's monster response. Read acquirement and wishing from separate, single copies: their blanking behavior resets the selected stack and can discard all remaining copies.

At the start of a game, each kind receives a different inscription from a pool of 30. The inscription identifies the kind consistently within that game, but is reshuffled for another game. It does not by itself reveal blessing or enchantment. An identified cursed scroll can also use a different name: for example, a scroll of destruction is cursed acquirement. Scroll of vulnerability is ambiguous, since both displacement and deflection use that cursed name.

Recognizing an effect and the game recording identification are distinct. Many useful non-cursed scrolls teach their type when read, but blank scrolls, hint sheets, law and dispelling do not automatically do so. A failed effect is not a reliable identification test. Jane's guide teaches the identities of one of six random categories; a scroll of identification reveals the selected copy's detailed state as well. Buying an identified item at the pawn shop also teaches its type. These methods avoid the risk and expense of reading an unknown scroll that turns out to be summoning, a curse, or a rare resource.

Choosing and preparing scrolls

For a new character, reliable escape and knowledge usually solve more immediate problems than maximizing enchantment. Teleportation escapes within a level; the warp changes dungeon levels but cannot reach the bottom floor; clairvoyance lets the player inspect a chosen region before approaching. None is interchangeable with unrestricted travel. Carry an escape scroll accessibly and keep a potion alternative for fear or blindness.

Blessing has especially clear value on acquirement, identification and teleportation: it changes what the player can choose or how much is affected. It does not make every scroll stronger. Summoning remains hostile, and positive blessing does not improve true sight's duration. Enchantment depends on the scroll's own enchantment value, and charging has its own charge formula and cap. Consult the particular item before paying to improve it.

Blessing also is not a universally safe way to remove curses. A sufficiently strong blessing can destroy a deeply cursed target instead of making it safe. Dispelling offers a different removal rule for items in use. Valuable equipment deserves an explicit comparison of these two methods before either scroll is spent.

Duration and repeated use

Some protection scrolls last for several ten-minute status updates, rather than a fixed number of actions. In ordinary indoor time these occur at ten-minute boundaries, so an effect used just before a boundary immediately loses one unit. Displacement and deflection replace their old duration instead of adding to it and can even overwrite a much longer equipment effect. See each article for its range. Most positive timed effects stop naturally counting down at 1000 units; this threshold is a property of the duration system, not a guarantee that repeatedly reading any scroll builds permanent protection.

Other interactions and older advice

Throwing an ordinary scroll does not read it at a monster. Its zero-damage throw can give it to a creature capable of carrying objects, or leave it on the ground. Blank paper has no normal writing command that turns it into a chosen magical scroll.

Older Omega guides describe exploits involving putting non-rings into ring slots to reuse their effects. The inventory rules in 0.90.4 reject those placements; carrying a scroll in a legal hand slot does not substitute for reading it. Older routes remain useful research leads, but their mechanics should not be assumed to work in this version.

Random inscriptions

The displayed names have the prefix scroll-. Six of these 30 inscriptions are unused by the 24 kinds in any one game; none has a fixed magical meaning.

Inscription	Inscription	Inscription
GRISTOGRUE	Kho Reck Tighp	E Z
Kevitz	Arcanum Prime	NYARLATHOTEP
Gilthoniel	Zarathustra	Ancient Lore
Eyes Only	Ambogar Empheltz	Isengard
Deosil Widdershins	Magister Paracelsus	Qlipphotic Summons
Aratron Samael	De Wormiis Mysterius	Necronomicon
Pnakotic Manuscript	Codex of Xalimar	The Mabinogion
Ginseng Shiatsu	Tome of Tromax	Book of the Dead
The Flame Tongue	Karst Khogar	The Yellow Sign
The Kevillist Manifesto	Goshtar Script	Pendragon Encryption

Generation probabilities

This table applies to the ordinary random-object generator, conditional on the final item being a scroll. Each cell is the probability of one particular kind at the indicated item level, not the combined probability of the column. The main catalogue supplies the level of every kind. Multiply by the number in the column heading to obtain that whole group's share. Values are rounded to three decimal places.

Source level	Level 0 (4 kinds)	Level 1 (5)	Level 2 (8)	Level 3 (3)	Level 5 (2)	Level 7 (1)	Level 10 (1)
0	14.790%	7.506%	0.221%	0.221%	0.221%	0.221%	0.221%
1	9.862%	6.607%	3.353%	0.099%	0.099%	0.099%	0.099%
2	6.485%	6.485%	4.345%	2.205%	0.065%	0.065%	0.065%
3	5.249%	5.249%	5.249%	3.517%	0.052%	0.052%	0.052%
4	4.831%	4.831%	4.831%	4.831%	1.643%	0.048%	0.048%
5	4.682%	4.682%	4.682%	4.682%	3.137%	0.047%	0.047%
6	4.474%	4.474%	4.474%	4.474%	4.474%	1.521%	0.045%
7	4.409%	4.409%	4.409%	4.409%	4.409%	2.954%	0.044%
8	4.346%	4.346%	4.346%	4.346%	4.346%	4.346%	0.043%
9	4.284%	4.284%	4.284%	4.284%	4.284%	4.284%	1.457%
10	4.225%	4.225%	4.225%	4.225%	4.225%	4.225%	2.831%
11 or higher	4.167%	4.167%	4.167%	4.167%	4.167%	4.167%	4.167%

Derivation and limits

For each attempt, the generator chooses the scroll category with probability 10/135, then chooses one of its 24 kinds uniformly. It accepts a candidate if its item level l is less than the source level d plus a uniform random integer from 0 to 2; otherwise it has a further 1% acceptance chance. Rejected candidates restart object generation, including category selection. The resulting acceptance weight is:

Item level relative to source	Acceptance weight a(l,d)
l < d	1
l = d	0.67
l = d + 1	0.34
l ≥ d + 2	0.01

The conditional probability of kind i is a(level(i), d) / sum(a(level(j), d), over all 24 scroll kinds j). Thus the pawn shop's level-5 source gives wishing about 0.047% of its generated scrolls, not 0.047% of every stock item. The 10/135 category weight is also not the final proportion of scrolls among all generated objects: rejection rates in every other category affect that proportion. Fixed monster possessions, corpse transformations and acquirement choices do not use this table. Source level is supplied by the generation event and need not equal the player's level or the displayed dungeon depth.