Improved Fireball

Improved Fireball/Invoked Devastation
School	Arcane
Type	Damage
Range	Missile/Ball
Base cost	30
Equivalent item	crystal of fire

Improved Fireball is an arcane offensive spell in ADOM. It allows the caster to throw a magical projectile on a designated tile which explodes in a ball of fire upon reaching its destination.

As the name implies Improved Fireball is a more powerful version of the Fireball spell and is ultimately a ball-type spell thus sharing the following common features:

• Effective range is approximately a circle (counting in tiles) with the radius based on PC's Willpower
• Attacking monsters with Improved Fireball while invisible will betray the PC's location to them
• Improved Fireball will damage everything in its effective area including monsters in walls and outside the PC's line of sight

Improved Fireball is the only spell in ADOM which can be targeted as a standard ranged attack. The projectile also behaves in the same manner as missiles/thrown objects — it will be stopped by walls, doors and other monsters if these happen to be in the flight trajectory.

Improved Fireball will not damage the PC even if they are caught in the explosion.

A large number of enemies in ADOM are immune to fire damage, making Improved Fireball useless against them (see the full list here). Some monsters are, on the other hand, highly vulnerable to fire (see the full list here). Improved Fireball is exceptionally powerful in the Frost Giant Jarl Caves.

As any other fire spell Improved Fireball is suppressed in the Ice Queen Domain. Attempting to cast it will drain the usual spell cost but produce no effect except an extra message.

See below for ball spell damage comparison.

Stats

Damage

Improved Fireball damage is dependent on PC's level (L) and spell proficiency (P). The exact formula is the following:

{2 + [(L + P) / 5]}d8 + L

Radius

Improved Fireball projectile explosion radius is solely dependent on PC's Willpower (W). The exact formula is the following:

max{2, [W / 8]}

Only every even value signifies a different blast size. Radius value should be divided by 2 and rounded down — the resulting number corresponds to actual circle radius counting in level tiles. In practice, the observable increase in spell radius will first occur when the PC reaches Willpower score of 32. Every 16 more points of Willpower (48, 64, etc.) will trigger another increase.

Ball spell radius 2, 3 (1-31 points of Willpower)
.......
.......
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Ball spell radius 4, 5 (32-47 points of Willpower)
.......
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.......

Ball spell radius 6, 7 (48-63 points of Willpower)
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Spell cost

Casting Improved Fireball costs its base value (30) which is increased/decreased according to active bonuses and penalties and additional value dependent on throwing distance (D). The exact formula looks the following way:

30 + ({D / 2} + 1) * 4

Distance points are calculated in the same way as ball spell radius (see schemes above for examples).

It should be noted that extra distance cost does not seem to be affected by spellcasting bonuses and penalties. This significantly decreases the spell damage/cost efficiency when choosing targets far from the PC.

Extra

Improved Fireball will destroy items on the floor, herbs, webs, and ice bridges.

Using Improved Fireball in the Animated Forest is not recommended as this will enrage all animated trees on the level.

Improved Fireball can be used to cook corpses and melt iron items into iron ingots. The corresponding item(s) should be lying on the floor for this to happen and may need several castings to be affected.

Ball spell comparison

Level 1 PC

Spell level	+0			+10			+20			+30
	Min	Max	Av	Min	Max	Av	Min	Max	Av	Min	Max	Av
Fireball	5	25	15	15	35	25	25	45	35	35	55	45
Ice Ball	5	29	17	15	39	27	25	49	37	35	59	47
Lightning Ball	5	33	19	15	43	29	25	53	39	35	63	49
Acid Ball	5	37	21	15	47	31	25	57	41	35	67	51
Improved Fireball	3	17	10	5	33	19	7	49	28	9	65	37

Level 20 PC

Spell level	+0			+10			+20			+30
	Min	Max	Av	Min	Max	Av	Min	Max	Av	Min	Max	Av
Fireball	27	62	44	37	72	54	47	82	64	57	92	74
Ice Ball	27	69	48	37	79	58	47	89	68	57	99	78
Lightning Ball	27	76	51	37	86	61	47	96	71	57	106	81
Acid Ball	27	83	55	37	93	65	47	103	75	57	113	85
Improved Fireball	26	68	47	28	84	56	30	100	65	32	116	74

Level 50 PC

Spell level	+0			+10			+20			+30
	Min	Max	Av	Min	Max	Av	Min	Max	Av	Min	Max	Av
Fireball	64	134	99	74	144	109	84	154	119	94	164	129
Ice Ball	64	148	106	74	158	116	84	168	126	94	178	136
Lightning Ball	64	162	113	74	172	123	84	182	133	94	192	143
Acid Ball	64	176	120	74	186	130	84	196	140	94	206	150
Improved Fireball	62	146	104	64	162	113	66	178	122	68	194	131

Some information taken with permission from Andy Williams' Guidebook.