Acid Splash 1e FAQ FAQ
Why is Acid Splash a 0-level cantrip in AD&D 1e?
The D&D Portal conversion uses level 0 because Unearthed Arcana introduced a true 0-level cantrip system for AD&D 1e Magic-Users. Acid Splash is deliberately reduced to only 1 point of acid damage so it can fit that apprentice-magic framework. This differs from the Portal 2e version, where the edition handles cantrips differently and Acid Splash is instead converted as a 1st-level Wizard spell.
The word cantrip has not meant the same thing in every D&D edition. In modern editions, it often means repeatable level-0 magic. AD&D 1e cantrips are also level 0, but they belong to a very specific apprenticeship and memorization system introduced in Unearthed Arcana. That system gives Acid Splash a plausible native 1e home, provided the damage is kept minor enough to remain cantrip-scale magic.
Unearthed Arcana cantrips are level 0
AD&D 1e Unearthed Arcana describes Magic-User and Illusionist cantrips as 0-level spells. Apprentice spellcasters learn these small magics before becoming normal 1st-level members of their class.
That makes level 0 an edition-native option rather than a modern rule imported backward from 3e or 5e. D&D Portal can therefore preserve Acid 
D&D Portal - Acid Damage type Acid is a damage type used by attacks,
spells, class features, resistance, immunity, and vulnerability. Full link: https://dnd-portal.com/rules/damage-types/acid/ Splash's identity as minor magic without inventing an entirely new spell tier.
The Portal conversion records the rules profile explicitly because not every 1e campaign necessarily uses the Unearthed Arcana cantrip subsystem.
A 1e cantrip is not at-will magic
Calling Acid D&D Portal - Acid Damage type Acid is a damage type used by attacks,
spells, class features, resistance, immunity, and vulnerability. Full link: https://dnd-portal.com/rules/damage-types/acid/ Splash a cantrip does not mean the caster can repeat it without limit. Unearthed Arcana cantrips are memorized resources and apprentices have a limited number available per day.
A Magic-User who reaches normal class level can retain cantrips, but retained cantrips continue to consume memorization capacity. Up to four cantrips can take the place of one 1st-level spell under that option.
This resource structure is a major reason the Portal page must not explain the 1e spell using modern assumptions about unlimited cantrip casting.
Why the conversion deals only 1 point of damage
Official 1e cantrips are intentionally minor. Person-affecting cantrips can cause pain, distraction, blindness, silence, or similar brief effects without functioning like ordinary combat spells.
D&D Portal gives Acid D&D Portal - Acid Damage type Acid is a damage type used by attacks,
spells, class features, resistance, immunity, and vulnerability. Full link: https://dnd-portal.com/rules/damage-types/acid/ Splash 1 point of damage as a deliberately conservative homebrew exception. That preserves the defining offensive identity of Acid D&D Portal - Acid Damage type Acid is a damage type used by attacks,
spells, class features, resistance, immunity, and vulnerability. Full link: https://dnd-portal.com/rules/damage-types/acid/ Splash while keeping each individual casting far below normal leveled damage spells.
Giving the cantrip a full damage die would become much more significant when several cantrips can replace one 1st-level spell. The fixed 1-point value prevents the conversion from becoming a superior way to split a normal combat spell into several strong attacks.
Why the 2e conversion is different
D&D Portal does not assume that adjacent editions should express the same spell with identical mechanics. AD&D 2e handles cantrip magic differently enough that the Portal version there is designed as a 1st-level Wizard 
D&D Portal - Wizard Character class An Intelligence-based prepared full caster with the largest spell-learning system, ritual flexibility, and subclass traditions focused on schools or specialist theories. Full link: https://dnd-portal.com/classes/wizard/ spell.
For 1e, the Unearthed Arcana 0-level structure is a better match for the concept. That version therefore trades almost all of the later spell's damage for the benefit of remaining genuine minor magic.
The difference is intentional edition-native design, not an attempt to claim that one of the two conversions reproduces a lost official Acid D&D Portal - Acid Damage type Acid is a damage type used by attacks,
spells, class features, resistance, immunity, and vulnerability. Full link: https://dnd-portal.com/rules/damage-types/acid/ Splash rule.