Loki is the Trickster God of Asgard, so it only makes sense that he is involved in numerous schemes within the Marvel Cinematic Universe. These schemes aren't always exactly evil, sometimes they are simply for a laugh. It's these plans that actually lead to Loki's slow journey from villain to anti-hero.
With a long history of plans, schemes, and tricks, it is only natural that some work out better than others. However, Loki is the Trickster God for a reason and so his plans are usually well-thought-out. The MCU would not be the same if it weren't for Loki's constant scheming.
Loki Pretends To Thanos' Army
In Avengers: Infinity War, Loki attempts to save the remaining Asgardians by trying to kill Thanos. This trick is a valiant effort, but there was little hope it was ever going to work. Loki has worked for Thanos before, and so Thanos understands how Loki operates.
It is unlikely he would ever consider allowing Loki on his team again. Thanos also already has two Infinity Stones at this point, so he is certainly more powerful than Loki could ever hope to be. Loki's heart is finally in the right place when he attempts to take down Thanos, but, unfortunately, it costs him his life.
Uses Mind Control On Erik Selvig & Clint Barton
This scheme works quite well, but it's lower on the list because it is not entirely Loki's plan. Loki knows how to utilize the scepter properly and is then able to control whole teams of people. He barely has to lift a finger in order for his plan of world domination to work.
Loki steps through the Tesseract's doorway and immediately finds the two people essential to his plan: scientist Erik Selvig and spy Clint Barton. While this plan is mostly a success (until the Avengers finally start working together) the scepter was given to Loki and he is technically working for The Other.
Meeting The Time-Keepers
This plan from the Disney+ series Loki is, quite frankly, a mess. Loki schemes to work with Mobius only to his variant self, and only to then meet the Time-Keepers and overthrow them. However, Loki is a bit out of his depth with the TVA and doesn't for many things. He quickly ends up taking a liking to Mobius that makes it a bit harder to betray him.
Loki also doesn't realize just how different his variant self will be from him. In the end, this scheme to control all time only ends with the destruction of the Scared Timeline. It is very likely that the failures of this plan will have more negative effects on the MCU than fans have seen previously. The Loki finale only left fans with more questions.
Stealing The Eyeball
Creating a scene and killing a man for his retinal scan in is a plan that actually works quite well for Loki in The Avengers. It allows Clint access to the materials Selvig needs and gets Loki in with the Avengers. This scheme is a smaller part of a bigger plan though, which is why it doesn't rank as high.
Most of Loki's plan depends on him getting captured by the Avengers and this is how he gets it done. Of course, at that moment in time, Thor was not a player yet and so did not come into play. His appearance almost ruins the plan, but eventually, everything gets back to Loki's liking.
His Plans During The Odinsleep
Odin falling into the Odinsleep in Thor wasn't exactly Loki's plan, but he runs with it as soon as it happens. Loki wastes absolutely no time claiming the throne for himself. This is the first scheme of Loki's fans get to see in the MCU. Loki finally reveals just how manipulative he is capable of being.
Even Frigga falls for this plan as she is too considered with Odin's health to really see what is going on. This scheme isn't higher because it heavily depended on events mostly outside of Loki's control that he then twisted for his own benefit.
The Snake Stabs Thor
As fans learned in Thor: Ragnorak, when they were children Loki turned into a snake as a ploy to stab Thor. Ironically, this seems to be one of Loki's most successful schemes. He knew Thor well enough to know that simply transforming into a snake would entice Thor.
Of course, Loki and Thor are gods so even as children, so a single stab was never going to kill Thor. It is more likely that Loki only meant to scare Thor and, considering the fact that Thor appears to still be caught up on it hundreds of years later, it certainly appears that Loki succeeded.
Loki Lets Frost Giants Into Asgard
After Odin fell into the Odinsleep, Loki took this opportunity to siege what he believed to be rightly his: the throne. To do so, Loki allowed Frost Giants into Asgard to kill Odin, so that Loki could then kill the Frost Giants and become both a hero and king. It is this yearning for approval and quick thinking that makes Loki one of the best characters in the Thor trilogy.
Of course, this plan did not work out the way Loki intended, but it is still a strong scheme. He had to think on his feet when Odin went into Odinsleep, and the plan he came up with was quite solid. If Thor hadn't met Jane and regained his honor, and therefore Mjolnir, Loki's plan likely would have worked.
Loki Disguises Himself As Odin
Thor: Ragnorak quickly reveals that Loki has been living on Asgard, disguised as Odin, since the Convergence. This is the longest scheme fans of Loki get to see as the time between the two movies is roughly four years. Loki obviously does not do a terrible job as king because the citizens of Asgard appear to be happy and Thor never had any reason to suspect otherwise.
The one flaw in this scheme was abandoning the Nine Realms to fend for themselves. This is what eventually gave Loki away to Thor, not to mention the large statues and bad plays dedicated to the, supposedly, dead Loki. The almost playful nature of this scheme just proves that Loki is the God of Mischief.
Loki Unleashes The Hulk
This is one of Loki's more brilliant schemes because even though the Avengers eventually catch they are still unable to stop it. Loki wants to unleash the Hulk because he knows the Hulk will tear the ship apart and hopefully ruin the Avengers. Loki uses his ability to manipulate even from his prison.
Every word he says has some kind of underlying meaning. He knows exactly what to say to each hero to get under their skin, so the plan is a success. Loki distracts the Avengers while Clint causes an explosion that turns Bruce Banner into the Hulk. While Loki's plan for world domination is not successful, this particular scheme is.
Loki's Second Death
Loki's best scheme happens in Loki has a tragic relationship with Thor, but he builds a rapport back with his brother and fights for what Thor believes is right to serve his own needs. In the end, he is able to fulfill both his and Thor's needs: Thor saves Jane and the realms, and Loki becomes king.
Loki exploits the brief camaraderie built between him and his brother by pretending to die. Thor's grief is then so strong that he doesn't question that this may be another trick. Loki then removes Odin from the throne and places himself on it. Thor no longer has to be king and Loki gets what he has always wanted. This doesn't last, of course, none of Loki's schemes do, but it's the closest to a success he ever gets.
