YMMV / Advanced Dungeons & Dragons 2nd Edition

• Game-Breaker:
  • D&D 2nd Edition Skills and Powers had a mage variant called Channeler, which effectively combined mage and sorcerer (you could learn as many spells as you wanted and cast them all however many times you wanted until you ran out of spell points). The only downside? You fatigued yourself when you cast a spell (and yes, you could kill yourself this way). There was an 8th-level spell called Heart of Stone that replaced your heart with a carved stone one. Among other effects, it made you completely immune to fatigue.
  • In the 2nd Edition of Dungeons & Dragons the Psionicist's Dimensional Door wasn't limited to vertically standing doors. Open a horizontal door below your target, put the horizontal exit above them. Let them fall for a while (the disorientation effect keeps them from casting or doing anything to save themselves). This either ends with the target being cut in half by a closing door or splatting against the floor. Good fun. Meanwhile the Psi is constantly getting EXP for expending power points. That's thinking with portals. That psionic power was also a popular means of drowning castles with their own moats or, with enough psionicists, the ocean. It was also a useful bomb delivery system, magical or otherwise.
  • If a character had a high strength, darts. Darts would add a strength modifier for damage and 3 attacks at range per normal attack. Normally, for a character with a reasonable strength score, their short range and measly damage made up for it. However, if a character had a very high strength score (such as an 18/76), the constant strength score to damage made it far more lethal than anything else you could use, and if a character had magically enhanced strength from a belt of giant strength or similar item, the damage output could look like something out of third edition. An Obvious Rule Patch in Player's Option limits the maximum strength damage bonus to the maximum damage roll of the weapon - in case of darts, 4, achievable at 18/76. But it also adds weapon mastery rules which allow all the more darts to be thrown, and at a greater damage, so...
• Good Bad Bugs: Until 3rd Edition, the description for the Cube of Frost Resistance said that inside the 10-foot cube it creates, "The temperature is always 65 degrees Fahrenheit," and that the cube only degrades if exposed to damaging cold. So, you could use it to walk through an unlimited amount of molten lava unharmed.

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