Galvanate's power is to give powers to others with a touch: specifically, he can render entire squads effectively invincible, along with strength enhanced enough to qualify the recipient as a Brute. Additionally he grants recipients an electric touch, strong enough to kill. While the invincibility is not strong enough to withstand Zion, people expressed hope his power would make some people capable of surviving a glancing blow.
While Galvanate's trigger event is unknown, Wildbow speculated it was in response to a single consistent but indirect threat to a group of individuals and involved electricity in some context, possibly in the form of machinery.
In the early-to-mid-nineties, Galvanate operated as a parahuman mafia enforcer before deciding to become a leader himself, which he did with great success using his powers. He was eventually captured and imprisoned in the Birdcage, where he became a cell block leader.
As a cell block leader, Galvanate attends the meeting where Marquis introduces Panacea, where he negotiates Panacea's services to cure toothache, as he finds the services of the dentist in cell block T too expensive.
↑ 1.01.11.21.31.41.5All in all, there were twelve cell blocks with leaders. That meant that there were eleven leaders with eleven lieutenants arriving. Acidbath, Galvanate, Teacher, Lab Rat and Gavel were leaders of the cell blocks on the men’s side of the prison. Lustrum, Black Kaze, Glaistig Uaine, String Theory, Crane and Ingenue were the female leaders. There were other cell blocks, but twelve was generally agreed on as a good number. It left room for discussion without too much chaos, and it left enough cell blocks leaderless that they had elbow room to do business elsewhere. - Excerpt from Interlude 16.z
↑ 2.02.12.22.32.4Galvanate appeared. He’d been one of a number of players that had supplanted the local organized crime in the early-to-mid-nineties. A mafia enforcer with powers who had decided he had what it took to be a boss. He’d done well, rendering entire squads of his soldiers effectively invincible, simultaneously capable of electrocuting someone to death with a touch.
Nothing short of Alexandria or an Endbringer would stand up to Scion’s sustained laser beam for even a heartbeat, but there was hope that Galvanate would render some people capable of surviving a glancing blow. - Excerpt from Extinction 27.3
↑ 3.03.13.23.33.4The question is essentially, 'What part of the Trump's trigger event determines the nuances of the resulting power?' In short, what was the relationship to powers at the time of the trigger event?
Galvanate grants invincibility, a brute effect, and an electric touch. Not so different from Usher; we can note that the power granted is consistent (one threat), but isn't a direct response/counter to the power (ie. isn't nullification/power resistance, so the triggeree isn't directly being affected by powers). It's possible that the enemy was a parahuman actively using their powers, but the trigger/threat was more indirect, and the threat was to multiple individuals (can grant power to many people). The involvement of electricity suggests a theme or context element. Machinery, perhaps? I picture a mob enforcer and his people fighting an enemy from another group, who is bombarding an area with incendiary shells and missiles. A tinker in a mech suit, firing off an endless barrage. Galvanate's group, his men, friends, maybe family, are all in danger as fire spreads and sections of building start to come down. Trigger. - reddit comment by Wildbow.
↑ 5.05.1“It seems that cell block C will be cooperating with us,” Marquis said. Then he smiled.
“Glaistig Uaine might see things, but she isn’t usually wrong,” Galvanate said. “She says the kid has power? Fine. Our issues are the usual. The dentist in cell block T charges a small fortune, and we’ve got some toothaches. Can you heal that?”
↑ 7.07.1Here and there, portals opened, and capes stepped onto the platform. String Theory, carrying only a laptop. Galvanate.
Galvanate reached out and touched a select few capes. Layering invincibility over invincibility for Alexandria, for Gavel, Gentle Giant, and a Birdcage cape I didn’t recognize. - Excerpt from Extinction 27.4
↑Galvanate Capable of granting invincibility and enhanced strength with a touch - Parahuman List, bolded edit by Wildbow.