Artifacts were uniformly colorless until 2007's Future Sight (and even then, only for Sarcomite Myr--colored artifacts would have to wait another year until Shards of Alara), meaning they could go in any and every deck. This presents a design challenge, as overpowered artifacts, from Masticore to Skullclamp to Umezawa's Jitte to Smuggler's Copter, could be universally adopted by every deck. Requiring certain colors of mana is a way to intrinsically balance the game, and artifacts sidestepped that entirely in the game's first decade. If Umezawa's Jitte had cost 1W or Masticore 2RR, they still would have dominated their respective formats, but they at least would have been restricted to decks capable of producing a given color of mana.

By Fifth Dawn, this problem with artifacts had grown critical. Ravager Affinity was destroying Standard, Skullclamp had been banned the same week as Fifth Dawn's release for its stranglehold on the format, and decks were showing up with twelve pieces of artifact hate in the sideboard--and sometimes the maindeck. Fifth Dawn was an attempted pivot--instead of colorless artifacts that slotted into every deck like Skullclamp, the set was full of artifacts that could be cast for colorless mana, but required colored mana to function at peak efficiency--cards like Cranial Plating, Vedalken Shackles, and Pentad Prism.

Mechanics of Magic: Sunburst

To mirror the set's five-color theme, Fifth Dawn introduced Sunburst, a mechanic that powered up artifacts based on the number of colors spent to cast them. This, of course, is antithetical to what artifacts had been up to that point, but Mirrodin Block was all about playing with the meaning of artifacts. Fifth Dawn played in that space by pushing you to play as many colors as possible, even if you were mostly using those colors to play artifacts.

Fifth Dawn was designed to be an intentionally weird set. There were massive creatures with huge drawbacks (Cosmic Larva, Desecration Elemental), a vertical cycle of Stations that went infinite with each other (Blasting Station, Grinding Station, Salvaging Station, Summoning Station), and a host of engines in search of a combo that turned one resource into another (Gemstone Array, Krark-Clan Ironworks, Clock of Omens). It was an attempt at correcting the issue with artifacts--i.e., if every deck could run a colorless card, then our designs should limit the decks that actively want those colorless cards. Skullclamp's only ask in deck design is: can I make one mana and do I run creatures? If the answer to both is "yes," then you run four copies of Skullclamp. Fifth Dawn wants you to ask much weirder questions, like "do I want to make my opponent shuffle their deck on demand?" and "can I make WWUUBBRRGG to make my opponent lose the game?"

To understand Fifth Dawn in all its weirdness, we must study Spinal Parasite.

The Insect is Magic's first and only creature with negative power and toughness. For five mana, we would usually expect to get a 3/3 or larger (Sand Golem, Thopter Squadron, Karn, Silver Golem). The Parasite is instead a -1/-1, a statline that had never before been printed, and hasn't been printed since, with Char-Rumbler as Magic's only other creature with negative power or toughness.

The art, out of the context of Mirrodin, is bizarre. Long before Edge of Eternities or Phyrexian Mites, Spinal Parasite was there on the rolling chrome fields of Mirrodin, blasting a laser out of its lamprey mouth, its metallic spines reflecting the light of the five suns. Nothing about this thing seems to intersect with the promise of Magic: the Gathering.

Spinal Parasite has Sunburst, one of Fifth Dawn's premier mechanics, meaning you could theoretically pay all five colors to get a 4/4, or, more realistically, a 2/2 for 2XYZ. You can then remove two counters to siphon a counter from another permanent, a pretty poor rate compared to a card like Hex Parasite (which is clearly modeled after our friend Spinal Parasite).

Even if you were to pay the full five colors for your Spinal Parasite, the best you could hope for it to cash in the four +1/+1 counters (thereby killing your Parasite) to take two counters off your opponent's Clearwater Goblet. The mana is difficult to hit and Spinal Parasite gives you only a self-sacrificing 4/4.

That's the problem with Sunburst--the Fifth Dawn cards assume you'd be paying the full chromatic spectrum for them, but that's a very iffy proposition, and one that was even more improbable in a world without shocklands, Triomes, Verges, or Mana Confluence. Back in 2005, you had City of Brass, Birds of Paradise, and a roster of lesser options like Tarnished Citadel and Grand Coliseum. Even the most casual decks that sought to exploit Sunburst and Fist of Suns and the Bringer cycle struggled to pull the mana together before the game ended, so the only Sunburst cards that saw any play were those that were good enough at two or three different colors. Skyreach Manta, as a difficult to cast 3/3 flier with upside, was good enough in Limited, and Infused Arrows made combat wildly frustrating, but in general, the mechanic didn't live up to its potential. Pentad Prism is a reasonable card, especially with the introduction of Proliferate, and Clearwater Goblet saw a ton of casual play as a proto-Cosmos Elixir. The best of the Sunburst cards is Engineered Explosives, an adaptable mass removal spell that can play the role of Pernicious Deed or a fast-acting Powder Keg. Of course, unlike those two, it'll never snipe a Titan, as the X is limited to the five colors of mana, but in tournament play, you're more than happy casting it for two or three.

The other Sunburst cards were mostly big beaters that were outclassed by preexisting creatures--Solarion and Suncrusher made you pay 2WUBRG and 4WUBRG to maximize them, and even then, they weren't impressive. Notably, Sunburst was a way to create massive artifact creatures while eliminating the dangers of Tinker and Show and Tell--Mirrodin block had given us Darksteel Colossus and Sundering Titan, and the Sunburst creatures required you to actually cast them, rather than cheat them into play. Tinker was defining Extended at the time, thanks to Darksteel Colossus, and so Wizards was looking for ways to make exciting artifact creatures that weren't useful in Tinker decks--hence, Solarion and Mycosynth Golem. It's a noble goal, but Sunburst didn't solve any issues, remaining a Limited-only mechanic and the core of one of the worst-performing Preconstructed decks Wizards had yet produced.

Sunburst then went dormant for almost twenty years*, with Battle for Zendikar's Converge serving as its closest analogue, before being brought back in Phyrexia: All Will be One and Edge of Eternities through Lux Artillery and Solar Array, respectively. The updated Sunburst now applies the status to a spell you were already casting, so it's pure upside and scales well to modern Magic. A Solemn Simulacrum cast off a Solar Array could be a 4/4 for 4 or bigger, and a Pinnacle Emissary cast with a Lux Artillery in play will be a beefy 5/5 for 1UR. This makes our modern Sunburst much closer to Converge, where Woodland Wanderer will always be a relatively respectable 3/3 for four, but can be a 6/6 for four, if you're willing to stretch your mana.

Even now, more than twenty years later, we're still fighting against the fundamental issue with colorless artifacts. Thankfully, Agatha's Soul Cauldron isn't posting Skullclamp numbers, but it's still omnipresent in the format. Sunburst may have been an imperfect solution for making colors matter to artifacts, but it was a valiant attempt to turn Mirrodin Block from an Arcbound Ravager wasteland to a chromatic wonderland, and that's worth recognizing. Certainly, the concept works--the two recent cards with Sunburst are great inclusions for decks with a heavy artifact component--and, as it encourages multicolor play and +1/+1 counters, both of which are consistent archetypes in Commander, I expect we won't have to wait another twenty years for Sunburst to return.

*Chamber Sentry effectively has Sunburst, but I don't expect anyone to remember that card.