Potions

A player drinks a potion by double clicking it, in the backpack or within 1 tile, in a bag on the ground too (“That is too far away for you to use”). Drinking needs a free hand: not a two-handed weapon, nor a weapon and a shield (“You must have a free hand to drink a potion.”). One potion of the stack goes, then its effect, with the sound of drinking and, for a human on foot, the gesture; an empty bottle comes back to the backpack, or to the feet when it is full. A potion that cannot be used up, such as one held on the cursor, does nothing.

What each potion does

Potion	Effect
Lesser heal, heal, greater heal	3 to 10, 6 to 20, 9 to 30 hit points; then 10 seconds before another heal potion (“You must wait 10 seconds before using another healing potion.”). Not drunk at full health.
Refresh, total refresh	A quarter of the stamina, or all of it. Not drunk at full stamina.
Strength, greater strength	+10 or +20 strength for 2 minutes, and as many more hit points at most.
Agility, greater agility	+10 or +20 dexterity for 2 minutes, and as much more stamina at most.
Night sight	Sight in the dark for 15 to 39 minutes, sent again when the player changes region.

A second strength (or agility) potion while the first lasts is refused: “You are already under a similar effect.”; so is a second night sight. When a bonus ends, the hit points or stamina above the new maximum go.

Explosion potions are thrown, not drunk: see Explosion.

Poison

A poison potion poisons whoever drinks it, at its level: lesser, regular, greater or deadly. A poisoned mobile loses hits every few seconds, its health bar turns green, it gets no hits back, and those around read that it looks ill; heal potions are refused (“You can not heal yourself in your current state.”).

Level	Damage a tick	Every	Ticks
Lesser	1 and 2.5% of the hits, 4 to 26	3 s	10
Regular	1 and 3.125%, 5 to 26	3 s	10
Greater	1 and 6.25%, 6 to 26	3 s	10
Deadly	1 and 12.5%, 7 to 26	4 s	10

The first tick comes after 3.5 seconds, and half the ticks repeat the damage of the last. A stronger poison replaces a weaker one; a weaker one changes nothing. The poison wears off (“The poison seems to have worn off.”), is cured, or kills; death ends it at once. It is saved with the character with the ticks it has done: logging out does not end it, it goes on at the next login. An NPC’s poison is not saved. A level 4, lethal, is there for monsters. A hidden poisoned player is not seen to look ill. Clients older than 7.0 do not draw the green bar.

Cure

A cure potion cures the poison by a chance; it is used up either way (“That potion was not strong enough to cure your ailment!”), and refused when the drinker is not poisoned (“You are not poisoned.”).

Cure	Lesser	Regular	Greater	Deadly	Lethal
Lesser cure	75%	50%	15%	0%	0%
Cure	100%	75%	50%	15%	0%
Greater cure	100%	100%	100%	75%	25%

Scripts poison and cure with mobile.poison(user, 2), mobile.cure(user) and mobile.poison_level(user).

Explosion

An explosion potion is not drunk but thrown. Double click it in the backpack or within 1 tile: one potion of the stack is armed in the backpack (“You should throw it now!”), a cursor opens, and a countdown 3, 2, 1 runs over whoever holds it, seen by those around, the first number after 0.75 seconds, then one a second. At 0 it explodes where it is: in the hand, at its holder; one held on a cursor goes off as soon as it is let go.

Throw it within 10 tiles and in sight (“That is too far away.”, “Target cannot be seen.” keep it in the hand, armed; double click it again to aim). It flies a tenth of a second a tile and the countdown goes on where it lands.

The blast hurts every living mobile within 2 tiles, the thrower too, with the rules of a blow: harming an innocent that was not fighting the thrower makes it a criminal, and a death names it as the killer. The other explosion potions within 2 tiles go off with it, without the thrower’s Alchemy. A thrower who left the game is blamed for nothing, and one’s own pets are no innocents to a blast nor turn on their master.

Potion	Damage
Lesser explosion	5 to 10
Explosion	10 to 20
Greater explosion	15 to 30

The thrower’s Alchemy adds a tenth of its points; a blast does at most 40. Scripts hurt the same way with combat.harm(target, damage, attacker).

Bonuses and night sight

A stat bonus is added to the base stat: the status shows the sum, combat damage and the weight a player can carry use it, and the maximum hits and stamina rise with it. Stat gains raise the base. Bonuses and night sight are never saved: they end when their time is up, when the player logs out, or when the server stops, and a save never writes the hits or stamina they held above the base maximums. An NPC’s maximums do not rise with a bonus.

Scripts give them with mobile.add_stat_bonus(user, "strength", 10, 120) and mobile.set_night_sight(user, 13, 1200); mobile.stats gives both the values with the bonuses and the base_ ones.

Potions are made by alchemy; the plain potions vendors sell and loot drops work as the named ones.

Change the rules

The potions are scripts/items/potion.lua: the table EFFECTS maps a template to its effect.
The templates with script_id = "potion" are the potions above, in templates/items/magic/potions.toml; the explosion potions have script_id = "explosion_potion" (scripts/items/explosion_potion.lua).

Existing roots

mgctl init never replaces a file you may have changed. Copy from the distribution scripts/items/potion.lua, scripts/items/explosion_potion.lua and templates/items/magic/potions.toml, or give script_id = "potion" to the potions a player drinks and script_id = "explosion_potion" to the explosion potions.

Not yet

Alchemy, poisoned weapons and the Poisoning skill, poisonous monsters, bandages that cure, the buff bar, potion kegs.