A wall is a point in the game where many players often get stuck at, often due to a sudden increase in the difficulty of the hardest unskippable mission. Ranks with skippable outlier missions are not included here.
Rank 44: Production difficulty suddenly ramps up, resulting in many players getting stuck here. Alf is needed to complete this rank in a reasonable amount of time, or it could take multiple weeks or longer.
Rank 93: This rank contains two Laboratory missions and a difficult potato mission, which both may need 2.1 M crit bonus to complete in a reasonable amount of time, although players with 524k bonus can get past it if their other cards are sufficiently leveled.
Rank 99: This rank has a bomber mission, an even harder bullet mission, and a tough placebo mission that requires comrade limited laboratories. This wall can be passed with 2.1 M bonus with enough patience, but can take weeks if not months with only 524k bonus. 8.4 M bonus is recommended to clear this wall in a short amount of time.
Rank 100: This rank and the next 9 ranks have comrade requirements that are about double the requirements of the mid to late 90s, greatly slowing progress for those who don't have good comrade generation. Jym 4 is recommended, although maxing the last 3 comrade rares would also work if Jym 4 is unobtainable.
Rank 126: This rank has two missions requiring AA's of Bombers, and a Cyborg mission. A discount of at least 10 B is recommended to complete these in a reasonable amount of crits. Manually critting Cyborgs is strongly recommended to complete this rank, however, those who have a discount of 100 B or higher can complete the Cyborg mission using comrades (100 B discount) or immediately upon unlocking Cyborgs (1 T discount or higher, unless they have dead Bullet production), skipping the AA bomber missions.
Rank 135: Players who have been consistently skipping the hardest missions (Sky Farms in the tens of trillions and Air Rescues) will struggle here. You must get 3 T Laser Drills if you can't complete the Air Rescue mission, which requires 9 T comrades. That mission alone can take about a week for players who haven't increased their Comrade production by much after ranks 110-115.