Wild Surge

A Wild surge is an event that occurs 5% of the time when a Wild Mage attempts to cast a memorized spell, or 100% of the time when they attempt to cast through Nahal's Reckless Dweomer. When a wild surge occurs, a 100-faced die is rolled, matching one of 100 rows in a table containing 100 effects. If the roll exceeds the mage's wild surge threshold, the effect from the table will replace the spell. Otherwise, the desired spell is cast.

Lore

Wild Magic is a young school of magic born after the Time of Troubles, as scholars started to study the wild magic zones created from the descent of so many gods on Toril. In such places, the Weave, a "fabric" that serves as a convenient interface letting casters more easily and more safely manipulate raw magic, has become damaged or distorted. Spells cast through the Weave in such a state behave differently, sometimes becoming more potent, sometimes being more difficult to aim as desired, or sometimes producing entirely unpredictable results.

Soon enough, Wild Mages became able to reproduce this phenomenon in areas where the Weave is intact. Since it involves a more direct manipulation of raw magic, it is harder not to make mistakes, mistakes don't just result in spell failure, and there seems to be an irreducible part of chaos to the process. As the mage shapes magical energy into the desired spell, a mistake or that irreducible part of chaos may get in the way and force them to release the raw energy in a sudden surge called wild surge.

As a way to lift the limitations on spellcasting that go in hand in hand with a full reliance on the Weave, Wild Magic is a promising school. Research focused on improving raw magic manipulation and reducing risk enabled the creation of items such as the Robe of Goodman Hayes or the Thayan Circlet, and spells such as Chaos Shield, Improved Chaos Shield and Nahal's Reckless Dweomer.

Nahal's Reckless Dweomer

• With this spell, the mage purposefully makes the raw magical energy surge with the intent of shaping it into any spell they understand, memorized or not, way over their level or not. If it is in their spellbook, they can cast it.
• Additionally, there is no issue with the residual energy that lingers around a mage or priest who just cast a spell: Through the dweomer, this energy is just re-used raw immediately, whereas normal spellcasting requires waiting for its dissipation before chanting another spell.
• Last but not least, because the surge was generated on purpose, odds that the mage will succeed in shaping the correct spell are increased by a value equal to their level.

Note: Casting this spell means a wild surge will occur, odds are not 5% but 100%.

Mechanics

Whenever a wild surge occurs, a D100 is rolled. The result is compared to a wild surge threshold. If the roll is strictly greater than the threshold, the wild surge table effect designated by the roll will happen. Otherwise, the Wild Mage succeeded casting the spell they wanted to.

The wild surge threshold is calculated as the sum of the following:

• A base value of 0, overwritten by either Chaos Shield, Improved Chaos Shield or Robe of Goodman Hayes
• A wild surge bonus, the only source of which being the Thayan Circlet
• The Wild Mage's level, only when Nahal's Reckless Dweomer is used

Note: The Wild Mage's +/- 5 level modifier does not affect the wild surge threshold, which uses the flat, unmodified level with NRD.

When a surge happens from normal casting, the surge table includes effects from row 1 to row 100. When the surge is triggered through NRD, it goes from 2 to 101 instead.

Highest odds to cast the desired spell

Original edition

In the original Baldur's Gate II: Shadows of Amn, several Chaos Shield spells can be made to stack when stuffed together into a single sequencer or contingency. This exploit allows a Wild Mage to drastically increase the odds that a wild surge be kept under control to cast the intended spell. Odds go up to:

• 100% through Nahal's Reckless Dweomer:
  • Chain Contingency with 3x Improved Chaos Shield, setting the base to 75
  • Level 23
  • +3 surges casting the right spell between #99 and #101.
  • -1 since surge #1 is not rolled over
• 80% while casting a memorized spell, counting #90 Area effect. That means odds to cast the wrong spell can fall from 5% to 1%.

Enhanced edition

In Baldur's Gate II: Enhanced Edition there is no such exploit, but the Wild Surge table may have been made more lenient^{[verification needed]} and the Thayan Circlet was introduced. The highest achievable odds to get the correct spell cast then seem to be:

• 77% through Nahal's Reckless Dweomer:
  • Improved Chaos Shield's base of 25
  • Thayan Circlet's +15
  • Level 31
  • +7 surges casting the right spell between #72 and #101, counting #90 Area effect
  • -1 since surge #1 is not rolled over
• 51% while casting a memorized spell -- not counting surge Oops, wrong target #48. That means odds to cast the wrong spell can fall from 5% to 2.45%.

Confusing aspects

It is useful to be aware the following:

• That random, harmless visual and sound effects are highly likely to occur on both caster and target whenever a wild surge occurs, even if the desired spell is cast
• That the target of the desired spell is retained or modified to fit the surge spell, following a set of rules

Targeting

Most of the 101 wild surges described in the table below entirely replace the spell that the Wild Mage was trying to cast. But there is one element that remains: the target.

A spell target can either be a creature or container, or a point on the ground. Single-target spells such as Blindness require the former type in order to be cast, whereas AoE spells like Grease demand the latter type. A sub-type of single-target spells require that the target creature be the self -- the caster -- like Mirror Image.

When a Wild Surge occurs and replaces the desired spell, the spell target may not be appropriate to the surge spell selected by the D100. The game uses the following rules to address that concern. If the spell target was:

• Self:
  • All surge spells use it as-is.
• Creature:
  • Surge spells that require a Self target will ignore it and just occur on caster
  • Creature surges will use it as-is.
  • Point surges will use the creature's position as their target point. Exception: Burst #76 will fail silently when the creature is not the caster.
• Point:
  • Self surges will ignore it and just occur on caster
  • Creature surges will be retargeted, even when the target point is a creature's position. A random creature in a radius 150% the size of the caster's visual range will be selected as the new target.
  • Point surges will use the spell target as-is. Exceptions: Burst #76 will fail silently if the target point is not the caster's position, and Invisible #29, Held #61 and Color change #98 will fail silently in all cases.

Wild surge effects

Below is the large table describing all possible wild surges.

Table notes

• Surges with None in the Target column affect the entire area and work regardless of spell target
• An Upheld value in the Target column is just a way to signal that the actual spell is going to be cast with its actual target unchanged, whatever it was
• For the Block or remove column, none of the means to block effects ever work on the caster for Self and Creature surges. This remains true even in situations where a Point spell gets randomly retargeted on caster due to targeting rules, since it becomes a Creature surge then. Means to remove effects do work, however.
• Spell Immunity never works on caster period, because it doesn't block a mage's own spells

Icon legend

In the large surge table below, icons are used to convey ways to either block or remove all of a surge spell's effects.

	Abjuration	Alteration	Conjuration	Enchantment	Evocation	Illusion	Necromancy
Spell Immunity:

Shorthand icons are used, regrouping several spells of a particular kind. The following icons mean that the following spells are effective against a surge:

• All sources of Protection From Evil
• Reflected Image and Mirror Image
• Stoneskin and Iron Skins
• Minor Spell Deflection, Minor Spell Turning, Spell Deflection, Spell Turning, Spell Trap and Shield of the Archons
• Minor Globe of Invulnerability, Globe of Invulnerability and Protection From Magic
• Globe of Invulnerability and Protection From Magic, but not Minor Globe
• Protection From Magic, but not the Globe spells
• All Spell protection removers
• All sources of Dispel Magic, including Protection From Magic *if* used after the surge spell took effect

 

Wild surge table

• In green are surges that let the desired spell be cast in desired conditions
• In orange are surges that need particular attention
• In blue is the one failed surge that's most often better than the desired spell
• A 15-foot radius describes an area the size and shape of a Fireball spell

Roll	Message	Effect	Target	Save or MR	Block or remove	File
1	Wild color changes	Caster shines and flickers for 1 turn	Self	No	No	SPWM102
2	Wild color changes	Caster shines and flickers for 1 turn	Self	No	No	SPWM102
3	Squirrels... Everywhere squirrels!	Summons 8 squirrels around caster for 2 turns	Self	No	No	SPWM103
4	I'm so itchy	Caster suffers a -2 penalty to casting time and weapon speed factor for 1 turn	Self	No	No	SPWM104
5	It's so bright!	Saturated colours on caster for 1 turn	Self	No	No	SPWM105
6	Area effect	The effects of the desired spell are applied to all creatures in a 15-foot radius centred on caster. Spells with an area of effect that triggers several times only get to have one trigger.	Self
7	Sex change	Caster's gender is reversed for 2 hours (see Bugs section)	Self	No	No	SPWM107
8	Color change	Caster turns golden for 1 turn	Self	No	No	SPWM108
9	What was that? Over there!	All in a radius twice the caster's visual range face towards the same point, that can be quite far away, where a "soul rising" animation is played	Self	No	No	SPWM109
10	Explosion?	Harmless fire effect on caster	Self	No	No	SPWM110
11	Entangled	Movement speed set to 0 and -2 AC penalty on caster for 1 turn	Self	MR		SPWM111
12	Slowed	Slow effect to all in a 15-foot radius centred on Point, for 1 turn	Point	No	No	SPWM112
13	Polymorphed	For 70s, target is affected by:  ① Polymorph Spirit Wolf: 100% resistance to Cold and Electricity  ② Create weapon: Magical +1, 4 APR, Normal Haste, spellcasting disabled	Creature	MR: ①		SPWM113
14	Held	Caster affected by Hold Creature for 70s	Self	MR		SPWM114
15	Hastened	Caster affected by Normal Haste for 1 turn	Self	No	No	SPWM115
16	Polymorphed	Polymorph Squirrel on caster for 40s: Spellcasting disabled, Base HP = 5, STR = DEX = 3, APR = 1 -- see Bugs section.	Self	vs Poly MR		SPWM183
17	Gold Destroyed!	80% of party gold is destroyed	Self	No	No	SPWM117
18	Weakened	Target suffers -6 Strength for 1 turn	Creature	No	No	SPWM118
19	Burst	The Sunfire spell bursts out from caster	Self			SPWI523
20	Legs... so... heavy.	Caster's movement rate reduced by 4 for 1 turn. (Base rate for player characters is 9.)	Self	No	No	SPWM120
21	Caster also targeted	The desired spell is cast twice: ① On target, ② On caster, where it affects all creatures in the potential AoE.	① Upheld ② Self
22	Held	Caster is affected by Hold Creature for 1 turn if they are humanoid	Self	vs Spell MR		SPWM122
23	Fear	All creatures in a 15-foot radius centred on Point are affected by Panic for 14 rounds. The caster is never affected.	Point	Spell -4 MR		SPWM123
24	Roll twice more	Roll twice more. If one surge modifies the target, subsequent surges will use the new target. Should #24, #46 or #63 be among the extra rolls, the target will not be modified a second time. No other characteristic than a once-modified target is inherited from previous surges.	Point
25	Area explored	The entire area is now explored	None	No	No	SPWM125
26	Globe of Invulnerability	For 7 rounds, target becomes immune to all spells of level 1, 2 and 3	Creature	MR		SPWM126
27	Silence	The Silence, 15' Radius spell is cast, centred on caster	Self	Spell -5 MR		SPPR211
28	Dizzy	Caster suffers from 100% spellcasting failure and -4 penalty to THAC0 for 1 turn. Innate abilities can still be used.	Self	No	No	SPWM128
29	Invisible	The Invisibility spell is cast on Creature target. Nothing happens if the desired spell used a Point target.	Point			SPWI206
30	Pretty sparkles	One of eight visual effects occurs on caster, while a harmless blue projectile flies towards Point	Self	No	No	SPWM130
31	Caster becomes target	The desired spell is cast but on caster, and all creatures are affected within the potential AoE	Self
32	Invisible	The Invisibility spell is cast on caster	Self			SPWI206
33	Colors!	The Color Spray spell is shot away from caster and towards Point	Point			SPWI105
34	I've always said that bird magic is the most difficult.	Summon 8 non-selectable birds on Point, they vanish after 2 turns	Point	No	No	SPWM134
35	Shouldn't this spell do something?	Only the visual and sound effects of the desired spell are "cast" on Point.	Point
36	Gems!	After a one-second delay, caster receives 3 to 5 gems among Aquamarine, Garnet, Horn Coral, Pearl and Sphene	Self	No	No	SPWM136
37	Berries in my pocket.	The legendary Goodberry spell is cast	Self			SPPR207
38	Berries in my pocket.	The legendary Goodberry spell is cast again and solves world hunger	Self			SPPR207
39	Projectile changed	A different projectile that carries the effects of the desired spell is hurled towards the target. AoE spells become single target and friendly fire becomes possible if it wasn't.	Creature
40	What's this in my pocket?	Rich random treasure created on caster	Self	No	No	SPWM141
41	What's this in my pocket?	Rich random treasure created on caster	Self	No	No	SPWM141
42	Combat ready!	All creatures in a 15-foot radius centred on caster receive a +2 bonus to THAC0 and damage for 1 turn	Self	MR		SPWM142
43	Combat ready!	All creatures in a 15-foot radius centred on caster receive a +2 bonus to THAC0 and damage for 1 turn	Self	MR		SPWM142
44	*hiccup*... *hic*...	All creatures in a 15-foot radius centred on Point get hiccups, suffering -1 penalties to THAC0 and weapon speed factor	Point	No		SPWM145
45	*hiccup*... *hic*...	All creatures in a 15-foot radius centred on Point get hiccups, suffering -1 penalties to THAC0 and weapon speed factor	Point	No		SPWM145
46	Roll twice more	Roll twice more. If one surge modifies the target, subsequent surges will use the new target. Should #24, 46 or #63 be among the extra rolls, the target will not be modified a second time. No other characteristic than a once-modified target is inherited from previous surges.	Point
47	Polymorphed	For 70s, caster is affected by:  ① Polymorph Spirit Wolf: 100% resistance to Cold and Electricity  ② Create weapon: Magical +1, 4 APR, Normal Haste, spellcasting disabled	Self	MR: ①		SPWM113
48	Oops, wrong target.	The desired spell is cast, aiming at a random creature selected within a radius 150% the size of the caster's visual range. Potential AoE is upheld, but friendly fire becomes possible if it wasn't.	Point
49	I feel refreshed.	The desired spell doesn't happen. Instead, caster recuperates as if they rested.	Self
50	Monsters summoned	The Monster Summoning II spell is cast on Point	Point			SPWI407
51	Is that snow?	If outdoors, it starts snowing. If indoors, turns into surge #46 Roll twice more.	None
52	What's with the noise?	The desired spell is cast on target with a faint thump	Upheld			SPWM155
53	Double Hit Points	The target's Hit points are doubled for 1 turn	Creature	No	No	SPWM153
54	Oops, a gate... Is that a pit fiend?!	Gates in this Nabassu on Point. It will vanish after 2 turns.	Point	No		SPWM154
55	What's with the noise?	The desired spell is cast on target with a faint thump	Upheld			SPWM155
56	Duration halved	The desired spell is cast on target but the duration is halved where applicable	Upheld
57	Swirly things	All creatures within a 15-foot radius centred on Point get a swirly smoke effect with a noise around them. It can repeat a few times but stops after 80s.	Point	No		SPWM157
58	Projectile speed halved	The desired spell is cast on target but both the projectile and the shock wave speed are halved	Upheld
59	Weapons glow	All wielded weapons in the area glow for 10s	None	No		SPWM159
60	No Save	The desired spell is cast on target and no saving throw is allowed against its effects	Upheld
61	Held	Creature target is affected by Hold Creature for 70s. Nothing happens if the desired spell used a Point target.	Point	MR		SPWM114
62	Detect magic	Any creature within a 15-foot radius centred on Point gets highlighted if it is affected by dispellable magic.	Point	No		SPWM162
63	Roll 4 more times!	Roll 4 more times. If one surge modifies the target, subsequent surges will use the new target. Should #24, #46 or 63 be among the extra rolls, the target will not be modified a second time. No other characteristic than a once-modified target is inherited from previous surges.	Point
64	Slowed	For 45s, all creatures in a 15-foot radius centred on Point are affected by the Slow effect and a -4 penalty to AC and THAC0 -- see Bugs section	Point	Spell -4 MR		SPWM164
65	Oops, wrong spell.	Instead of the desired spell, a different spell is cast on target, selected randomly from a pool of spells of the same level. Spells from the pool don't need to be known by the caster. The contents of the pools are unknown to this Wiki.
66	Lightning bolt.	The Lightning Bolt spell is cast at the target.	Creature			SPWI308
67	Strengthened	Target benefits from a +6 Strength bonus for 70s	Creature	MR		SPWM167
68	Heal	An AoE version of the Heal spell is cast, affecting all creatures in a 15-foot radius centred on target	Creature	MR: • Heal • Cure Intox		SPWM168
69	Entangle	Movement speed set to 0 and -2 AC penalty on target for 1 turn	Creature	MR		SPWM111
70	Weakened	Caster suffers -6 Strength for 1 turn	Self	No	No	SPWM118
71	Fireball	The Fireball spell is cast, centred on Point	Point			SPWI304
72	Turned to Stone	The Flesh to Stone spell is cast on target	Creature			SPWI604
73	Spell cast and I feel refreshed.	The desired spell is cast on target and the caster recuperates as if they rested	Upheld
74	Heal	An AoE version of the Heal spell is cast, affecting all creatures in a 15-foot radius centred on caster	Self	MR: • Heal • Cure Intox		SPWM168
75	Dizzy	Target suffers from 100% spellcasting failure and -4 penalty to THAC0 for 1 turn. Innate abilities can still be used.	Creature	No	No	SPWM128
76	Burst	The Sunfire spell bursts out from Point, but only if that's the caster's position. Nothing happens otherwise, though multi-roll #24, #46 and #63 will fix that if a surge preceding #76 retargeted on caster.	Point			SPWI523
77	Held	Target is affected by Hold Creature for 1 turn if they are humanoid	Creature	vs Spell MR		SPWM122
78	Blinded	Target is affected by Blindness for 2 hours	Creature	vs Spell MR		SPWM178
79	Charmed	Target is affected by Charm Creature for 1 hour. Elves have a 90% chance to be unaffected and Half-elves 30%. Contrary to most charm spells, blue-circled creature will not become hostile when this spell wears out.	Creature	vs Spell MR		SPWM179
80	Gems!	After a one-second delay, 3 to 5 droppable but unstealable gems are created on target. See #36 for the list.	Creature	No		SPWM136
81	My legs! What have you done?	Target's movement rate reduced by 4 for 1 turn. (Base rate for player characters is 9.)	Creature	No	No	SPWM120
82	What's in my pack?	Droppable but unstealable Rich random treasure created on target	Creature	No		SPWM141
83	Silence	The Silence, 15' Radius spell is cast, centred on Point	Point	Spell -5 MR		SPPR211
84	Silence	The Silence, 15' Radius spell is cast, centred on Point	Point	Spell -5 MR		SPPR211
85	Sex change	Target changes gender for 2 hours. Many creatures will be unaffected. (See Bugs section)	Creature	No	No	SPWM107
86	Explosion?	Fake, harmless Flame Strike on target	Creature	MR: • Flame		SPWM186
87	Stinking cloud	A Stinking Cloud-like spell centred on Point. The only difference with the real spell is that Elves have a 90% chance to be unaffected by this surge, and Half-elves 30%.	Point	Death +2 MR		SPWM187
88	COW!	Cow falls from the sky for 3d10+3 crushing damage on target. The cow may explode on impact in a thunderous noise, dealing a shock wave blow to the target and all within a varying radius. Walls break the spread of AoE attacks.	Creature	MR		SPWM188
89	Dizzy	Target suffers from 100% spellcasting failure and -4 penalty to THAC0 for 1 turn. Innate abilities can still be used.	Creature	No	No	SPWM128
90	Area effect	The effects of the desired spell are applied to all creatures in a 15-foot radius centred on Point. Spells with an area of effect that triggers several times only get to have one trigger.	Point
91	Itchy	Target receives a -2 penalty to weapon speed factor for 80s. Note: The visual effect can be negated with an odd save vs Polymorph.	Creature	vs Spell MR		SPWM191
92	Hit Points doubled	The caster's Hit points are doubled for 1 turn	Self	No	No	SPWM153
93	Held	Target is affected by Hold Creature for 1 turn if they are humanoid	Creature	vs Spell MR		SPWM122
94	Hastened	Target affected by Normal Haste for 1 turn	Self	No	No	SPWM115
95	My gold!	80% of gold on the target is destroyed	Creature	No	No	SPWM199
96	Spell cast twice	The desired spell is cast twice on target	Upheld
97	Spell cast, +4 save	The desired spell is cast on target; victims make any Saving throws against it with a +4 bonus	Upheld
98	Color change	Creature target's skin turns red for upwards of 3 years. Sounds like Neera's got something like that. Nothing happens if the desired spell used a Point target.	Point	vs Spell MR		SPWM198
99	Spell cast at double level	The desired spell is cast on target, but at double the caster level. Note: The growth of most spells caps at level 20, but higher caster level makes them harder to dispel.	Upheld
100	Spell cast normally	The desired spell is cast on target	Upheld
101 (9B)	What was that? Over there!	The desired spell is cast on target	Upheld

Tips

• The Fireshield (Blue) and Fireshield (Red) spells will never surge. If cast through the Reckless Dweomer, they will always get surge #100 Spell cast normally. That makes them level 1 spells that don't even need to be memorized.
• It seems safe to romance both Neera and Hexxat at the same time in a single playthrough, without consequence, which is possible because of the bug with surges Sex change #7 and #85. Since Hexxat only romances females and Neera males, it seems that Beamdog developers didn't bother writing a conflict for this pair.

Bugs

• Burst #19 and #76: Like the real Sunfire spell, these surges will have no effect if the casting command is given while the character is walking and casting speed is 0.
• Entangle #11 and #69: When combined with #20 Legs... so... heavy. or #81 My legs! What have you done? on the same creature, they can make it move at teleporting speed.
• Polymorphed #16: The character turned into a squirrel will retain an effect that sets their Attacks per round to 1 even when back to human form. Since it lasts for 500 days, it is advised to dispel this effect. Dispel has a chance to fail, however. A player could verify that the effect has been removed by equipping a weapon that sets attacks per round to something else than 1. If APR remains 1, the effect was not dispelled. Any dart will do. Boomerang Daggers will not.
• Sex change #7 and #85: These surges can trigger companion romance if they affect the protagonist. This romance will continue even after the sex change is reverted.
• Slowed #64: When the victim succeeds in their save roll, all effects are negated. But the slowed sound and portrait icon are still applied.

TODO

• Confirm with further in-game tests the accuracy of the table's column Block or remove when casting each of Self, Creature and Point spells. ^{[verification needed]}
• Check differences between the current data, which was researched on BG2EE 2.5.16.6, and the original edition of Baldur's Gate II with Throne of Bhaal
• Research which spells of each level can be randomly selected by Oops, wrong spell #65, and under which targeting conditions. It doesn't seem to be the whole array that's made available.

Sources

• Near Infinity
• In-game tests
• Baldur's Gate: Wild Surge Table