While Rick and Morty doesn't restrain itself in depicting the chaos that results from Morty's well-intentioned but disastrous decision to save an interdimensional entity, there was one final tragedy that didn't become apparent until much later.
In the Season 2 episode "Mortynight Run," Morty is horrified to learn that Rick has been supplying weapons to Krombopulos Michael, an enthusiastic assassin on his way to kill a gaseous entity under heavy guard. Morty's resulting intervention accidentally kills Krombopulos, and his efforts to free the entity - now called "Fart" thanks to Rick - only results in more death and destruction. Tragically, Morty ultimately chooses to kill Fart after learning of its intention to destroy all carbon-based life, but the matter at least appears to be closed... until Rick and Morty encounter Krombopulos Michael's wife.
The Rick and Morty comics elaborate on the fate of Krombopulos Michael's wife Krombopulos Amy, whose picture he briefly glanced at during his final mission. In Rick and Morty #34 - from Kyle Starks, Allison Strejlau, and Crank! - fans see Amy learn of her husband’s demise, preparing to track down her husband’s executioner. In Rick and Morty #41 and #42 “Rick Revenge Squad” - by Starks, Crank!, Sarah Stern, and Marc Ellerby - Amy is among a group of powerful individuals seeking revenge against Rick. After pursuing Morty, Krombopulos Amy is stopped from killing him by Rick, who asks her if killing a kid is really going to make her feel better. After breaking through her anger and making Amy realize her mission is misguided, Rick signals to Morty that he better kill her with her discarded weapon while her guard is down.
While her hesitation proves she isn't a gleeful killer like her husband, it's left unclear whether Morty ends his accidental killing spree by taking out Krombopulos Amy at Rick's instruction. However, it would be well within the show's tone for Morty to regretfully pull the trigger, knowing that other threats were right around the corner and that when traveling with Rick, nothing is certain, especially a ceasefire.
One of Rick’s biggest flaws is that his actions constantly result in horrific consequences that have created an army of enemies. While Rick has the intelligence and lack of moral ethics to handle them, Morty’s attempt to do better than his grandfather only ended up following in his footsteps. Although Morty simply wanted to save an innocent, the deaths that followed attempting to save Fart proved to be all for nothing when Morty killed him, despite it being for the right reasons. The decision came back to haunt him in the form of a grieving wife who took up her husband’s profession simply to be close to his memory.
Whether Krombopulos Amy is spared or killed, it's hopefully the case that the consequences of Morty's rampage are finally over. Rick and Morty has argued again and again that the universe is vast, complex and cruel, and that even kindness can have horrific consequences - something that's abundantly clear as Morty's sins lead to yet more chaos and death.