This exploit relies on how getting items from a mission works. Get the Plasma Pistol on the first mission Select that unit again then change weapon to primary.Move & Overwatch with Sniper Rifle without Snap Shot skill

or using Mind Control for Psionic alien.or using grenade, Poison Spit or Rift if units are in closely tight and within abilities range area of damage.any of your unit is in the open or flanked.The aliens will not move and not take any action, but Overwatch and flanking or alien has no cover The aliens will not move, but will take Overwatch or shoot if your unit is in cover have total less than 50% chance. Later game with Iron Will and this recruiting method you will guarantee all your soldiers have over 100 Will and thus very high chances of being Psions and being very hard to control when facing enemy Psionics. Also training Squaddies is actually much easier when you don't need to babysit them as much, them being able to hit enemies from medium distances with reasonable certainity and high Will means they won't panic immediately when fired upon, taking slight damage or even if somebody is killed next to them. This means that your Assaults can snipe enemies from longer distances even with shotguns, Snipers basically never miss and your Heavies can actually hit something. This will hugely help your late game as you get usually one or two 80 aim and 50+ will soldiers per recruiting cycle (3 days) and 80 aim means +15 increase from the basic 65 aim that equals 1.5 S.C.O.P.Es. Again when you have 10+ of these, start firing everything with less than 50 Will and 80 Aim and last when you have Iron Will and New Guy unlocked, start recruiting only Squaddies with 80 base Aim (for Squaddies meaning 82 Heavy, 85 Assault and Support, 90 Sniper) and 60+ Will (can go as high as 68 for Iron Will Squaddies). Simpy recruit full batch and when they arrive, immediately fire all Rookies who have less than 50 Will and 70 Aim and when you have 10+ of these, start firing all Rookies who have less than 50 Will and 75 Aim. When you have no shortage of funds (later in game or with fund cheat), you can farm for high stat level soldiers. Not Created Equally Second Wave option creates another nice exploit. Would be even easier cheat if the game would have quick load. Obviously these cheats won't work in Ironman mode.

Quick save before any movement and load if aliens encountered for optimal placing or to unawaken any extra alien groups encountered. Quick save and load mechanism allows also safe dashing scouting of map. Just quick save before shot and reload if missed or done too little damage. Save Scum Second Waveoption allows a cheat in aiming.

5 Get the Plasma Pistol on the first mission.

Xcom enemy within save editor