Eringya's Noxious Bog

Version 0.31: This article may not be up to date for the latest stable release of Crawl.

Eringya's Noxious Bog
Level	6
School1	Alchemy
Source(s)	Fen Folio Great Wizards, Vol. II
Casting noise	6
Spell noise	0
Power Cap	200
Range	4
Flags	Area, No ghost

Causes the caster to release a torrent of sludge that transforms nearby areas into a toxic bog. The sludge damages and poisons all monsters, even those resistant to poison. The bog cannot form on areas adjacent to multiple solid features, nor on areas that lack solid floor, like deep water or lava. The transformation is temporary and cannot be sustained out of the caster's sight. Spellpower will increase how long the bog lingers.

Eringya's Noxious Bog is a Level 6 Alchemy spell that temporarily converts tiles near the user into toxic sludge.

Useful Info

When cast, Eringya's Noxious Bog gives the Bog status. All valid floor tiles within a 4-tile radius are converted into toxic sludge. This spell requires open space; tiles that are next to more than one solid feature (like walls, trees, statues) are not converted. Deep water and lava are unaffected. However, it does cover non-solid features such as stairs, escape hatches, shops, and traps, preventing them from being used.

The sludge acts like shallow water, but it will damage and poison non-flying creatures. The bog itself deals 4d6 damage (70% poison, 30% physical). If the bog dealt any damage, it additionally causes an extreme amount of poison to non-immune monsters. It deals 4 "stacks" of poison (the maximum) to monsters without poison resistance, and 2 "stacks" (half-max) to monsters with poison resistance. Resistance doesn't reduce chance of being poisoned, just the amount of poison. Bog damage and poison are not impacted by spell power.

Flying creatures are completely immune to the bog. The caster is immune to the damage, but still gets the penalties (if any) from being in shallow water.

Casting Ignite Poison will create short-lived flame clouds above some bog tiles (33% chance per tile). These in turn will create clouds of steam.

The bog status lasts for 3 + 1d(2 + pow/10) turns. If you leave line of sight of a bog, it reverts back to regular tile. If you leave the level, the bog status ends immediately. This spell cannot be recast while active.

Strategy

Eringya's Noxious Bog is a level 6 spell, that does not work outside open areas, blocks staircases, has a range of 4, does nothing against flying or poison-immune opponents, and penalizes you if you can't fly/swim. But, even with all these limitations, this spell can be worthwhile due to its strengths.

It combos incredibly well with Ignite Poison. With Bog active, Ignite Poison is strong and MP-efficient; anything without immunity to poison/fire will take massive damage every turn. Against non-resistant monsters, Ignite Poison does 8d14+ damage per cast, ignoring both AC and EV, plus the damage from the bog and clouds. Poison resistance reduces the poison by half; either 2 turns for full damage, or 1 turn for half damage. Even monsters with both rPois and rF+, such as tentacled monstrosities, will end up dying to 2-4 casts.

Overall, it's definitely not a spell that can be used to kill everything. Instead, it's best thought of as a "side" spell - use it to deal with non-fying, non-poison immune enemies in an efficient manner. Also, without Ignite Poison, it becomes a lot weaker, but still alright.

Tips & Tricks

• While you are slowed by the bog's water, any non-flying non-swimming non-large monsters are penalized in the same way. The bog will make it harder to escape from ranged attackers, but it is not as bad as it initially seems. If all else, a potion of flight works.
• As the bog covers traps, you can use this spell to prevent enemies from stepping on unfortunately-placed traps. However, you won't be able to use it to bypass traps in narrow corridors (such as the entrance to Zot:5's orb chamber).
• The bog counts as shallow water, meaning other sorts of fire attacks can be used to create LOS-blocking steam.
• Note that the bog doesn't deal damage on the turn it's created.

Trivia

This spell refers to a mage called Eringya; it is the first reference to them in-game since the removal of the spell Eringya's Surprising Bouquet and the wizlab level Eringya's Formal Garden (which has now been re-introduced).

History

• Prior to 0.31, Eringya's Noxious Bog was a dual-school, level 6 Poison Magic/Transmutations spell.
• Prior to 0.28, Eringya's Noxious Bog did not place a bog under the caster, as they were not immune. It also did not place a bog in tiles next to any solid features.
• Prior to 0.26, Eringya's Noxious Bog would cause the caster to leave toxic bog tiles behind them as they traveled. Additionally, Ignite Poison always created flame clouds over bog tiles and for a much greater duration.
• Eringya's Noxious Bog was added in 0.25.