Duncan Ferguson made the first ascent of the Squid in 1977 with Doug Snively. Though Ferguson is not as well known as some other Boulder-area climbers of the 70s, like David Breashears, Ferguson made many notable first ascents, including the first free ascent of the Naked Edge.
As an ice climber, Ferguson has excelled at putting up steep, very thin ice and mixed routes, which is what the Squid is. The climb is in a right facing dihedral, and can form as anything from a sustained sheet of steep, difficult to protect ice to a mixed climb done on a series of hanging icicles.
Ferguson and Snively made one unsuccessful attempt at climbing the route before returning and succeeding. In the classic Glen Randall book Vertigo Games, Ferguson said of the first attempt, "We chickened out. It got terrifying. The whole thing is poorly bonded, and it's ultra-steep and thin."
When the main ice pillar is in, there are usually difficult mixed variations off to the side that can be attempted. Because the quality of the ice is often bad and protection can be difficult, climbers sometimes use rock gear off to the side of the ice. The first pitch is the crux, and is long and sustained. The second pitch is a shorter, only 40 feet or so, and more moderate.
Approach the Squid by hiking to Emerald Lake and continuing on, then looking for the climb on the hillside above on Flattop. Hike up the climb from the trail. You can either rappel off or walk off from the top to the west.