Congrats to Kevin Brennan for winning James Maliszewski’s first Grognard’s Challenge. The magic item Mr. Brennan invented, the devil’s eye, out-old-schools the magic items of Arneson, Gygax, etc. :
It's the kind of item that reminds you that magic isn't something to be trifled with and that every boon it grants might come with a price. More to the point, there's an actual temptation to use this item, because the boon it offers is a good and useful one. It's a screw job that players will seriously consider using rather than just a game mechanic designed to emulate a screw job (like cursed swords).
Mr. Raggi gives it very high praise as well:
Cool... aside from basic potions and scrolls, none of the magic items in my current campaign (not that the PCs have seen a single one after three sessions), or in my upcoming (at some point :P) adventures, are wholly beneficial.
A great way to keep people on their toes and prevent players from even wanting to be decked out like a Christmas tree.
Yeah, it does that as well, but as Mr. Maliszewski points out, magic that refuses to simply do as it’s told has strong traditional roots in the literature, and this goes beyond pulp. Yes, there are echoes of Moorecock’s Stormbringer and Silke’s interpretation of the Death Dealer’s horned helmet, but an even closer parallel can be drawn to Tolkien’s palentirs, the Ring of the Nibelung, or the favor of the Greek gods.
This is one area where most games, pen-and-paper RPGs and, most especially, computer RPGs alike, almost all stumble, and in the exact same way. By making magic predictable, reliable, and easily controllable, they drain all the color from it. Fireballs not only harm just your enemies, they don’t cause fires to break out or melt the treasure the monsters were carrying. Stored magical power doesn’t leak or cause unexpected effects. Magic is far more reliable and boring than technology; your computer might blue-screen, your light bulbs might pop, and your car may be melting the polar icecaps, but your wand of lightning bolts only ever does 6d6 points of damage to your intended targets.
Battling the complacency this creates was part of why I created residual effects for spells in my Moldvay/Cook/LL hack. Tailoring these sorts of dangers can go far to bridge the power gap between magic using and mundane classes. They can slow the power creep that comes from the Christmas tree effect. Most importantly, they make magic something that is used with thought and careful consideration. In short, it makes magic magical again.UPDATE: Jeff riffs on this same theme.