|The acid mound squelches softly across the ground, leaving a trail of acidic goo in its path.|
An Acid Mound is, as it's name implies, acidic. It will corrode your weapon each time you hit it, and it will corrode your armor each time it hits you. Each corrosion event removes one level of enchantment. A +1 sword will become +0, a suit of +0 armor will become -1, etc. Aside from its ability to ruin perfectly good equipment, the acid mound is mostly harmless.
However, corrosion is bad, and if you allow it to happen repeatedly your once useful equipment will quickly turn to junk. This is why, if you try to attack an acid mound with an unprotected weapon, the game will warn you of the potential for damage to your weapon and give you a chance to reconsider. The message will not appear if you cannot see or cannot identify the acid mound. In most cases, you should heed the warning. (In versions prior to 1.7.4 there was an exception to this: if you executed an attack on a regular creature but your weapon had a broader attack (like an axe or spear) you would receive no warning if an acidic creature was in the extended attack zone).
You can easily tell which of your items have been protected against acid; in the inventory screen, they will have a } (curly brace) instead of a ) (parentheses) next to their reference letter. It is also spelled out in the item's written description.
If your equipment is protected, you've got nothing to worry about. If not, keep reading.
Tactics against (for those with unprotected equipment) Edit
- Avoidance. (run away).
- Ranged attacks. (darts, javelins, potions, staffs, kitchen sink).
- Ally power. Let your allies handle it, they aren't affected by acid.
- Go negative. Negating the bastard means no more corrosion.
- Bare fisted fighter. Unequip your weapon and armor (command is 'r' for remove) and fight hand-to-mound. It's surprisingly effective as long as nothing else is harassing you. If you find an acid mound with no warning, first remove your armor rather than your weapon to avoid getting damage to either.
- Get wasted. Wield a weapon you won't miss when it gets ruined. Also, don't forget to remove your armor. And, don't forget to toss the weapon when you're done. Most importantly, keep an eye on the numbers as you go, a heavily corroded weapon may be worse than no weapon at all. Beware of wielding unknown (possibly cursed) weapons.
- Negation will remove good and bad magic from your items, setting them to +0. Corrosion, surprisingly, qualifies as bad magic! If your equipment was degraded, you're past the early depths and you have nothing else available, drop the corroded items and use a Scroll of Negation (or, if possible, the appropriate Charm).
- Safety first. If you've got the scrolls, protect your equipment beforehand. Duh.
| The charming inhabitants of the dungeon: