OK! I'm a bit late to the party.
*cracks fingers*
TL;DR:
Turn based strategy games:
Divinity original sin 2, Civ V.
Real time strategy games:
Stellaris, Red alert 3.
First person shooters:
Doom 2016, Gunfire reborn, fallout new Vegas.
Rogue like/lite:
The binding of isaac repentance, Risk of rain 2.
Point and click games.
Deponia series.
souls like:
Dark souls 1, Salt and sanctuary.
card games:
Yu-gi-oh (duel nexus with friends).
platforming games:
Super Mario maker.
NOT TL;DR
Divinity original sin 2 : it is a game i highly recommend you play with a friend as it has local and online co-op. it is a story rich RPG where you could play as a total of 4 players but i found the most fun playing as 2 "lonewolf" players as it brings a bigger challange. you get to chose what elements of magic your character is able of using apon every level up. max level is 20 but you will most likely finish the game at lvl 19 as you need to do alot of side quests as well as a littl bit of "murder hobo" gameplay to reach level 20. the only gripe i have about the game is the stat bloat from levels. you are going to be outnumbered 9 times out of 10 and the enemies being 1 level higher then your characters is going to make the fight challenging, if they are 2 or more levels higher then you , then the fight will be from very difficult to impossible.
Civ V: a strategy game with many win conditions. Be it conquest, science, religion, etc. you chose what type of victory you are planing on achieving then i highly recommend googling a civilization that would be proficient at achieving it. the rest i would recommend learning by playing the game.
Stellaris: RTS version of Civ V... i would recommend playing CIV V before Stellaris because Stellaris is far more fast pace. its got a pritty mean learning curve but its well worth the trouble. you create your own species of alien and control the stars. watching a short tutorial video is recommended.
Red alert 3: a classic RTS with great music, gameplay, and ok balancing. if you dont feel like playing the game at least listen to the games sound track.
Doom 2016: if you want to "relieve stress after stressful working hours" then DOOM is definitely the game for you. its a game where you keep moving and shooting. the moment you stop moving, you die.
Gunfire reborn: a game that is a combination of an FPS and a rogue lite you slowly get better at the game with experience as well as unlocking new passive buffs for your characters.
fallout new Vegas: a game where you traverse the Mojave finding mysterious things all over whiles getting stronger as you level and find better equipment for your specialization. highly recommended.
The binding of isaac repentance: repentance is the newest and best DLC the game has gotten by FAR. but the game by default is good too. you start off with one or two items (based on the character you chose) and as you progress you will find random items strengthening you in different way. some just increase stats others change the way you attack. different areas have different item pools. if you defeat the floor and its boss without taking any red heart damage. then you have a very high chance of a devil deal door to spawn in witch you can trade some of your max hp for powerful demonic items. if you choose to not go into the devil room and are able to clear another floor and its boss without taking red heart damage then you will have a very high chance of getting an angel room in witch you will get one powerful holy item for free. i leave the rest for your experimentation.
Risk of rain 2: very similar to binding of isaac, but its 3D.
Deponia series: i don't want to spoil anything so ill just say it is the best set of point and click games i have ever played.
Dark souls 1: in my opinion it is the best souls game (game where you drop your collected souls apon death but you can pick them up on your next respawn) out there, having the best map design as well as making armor actually matter in the game. one of the more challenging games on the list.
Salt and sanctuary: a 2D version of dark souls with by FAR the BEST local co-op mode i have ever seen a game have. its also challenging but playing it with a friend via couch coop or (online) local coop via Parsec(a program that lets you play local coop games online).
Yu-gi-oh (duel nexus with friends): specifically on a website called dueling nexus. because most websites/games you have to buy packs with micro-transactions (IRL $ for some PNGs)
while on dueling nexus everyone has all the cards unlocked so building a deck is up to your imagination rather then how much money you spent.
Super Mario maker: a Mario game where other people make the maps, at this point there are more maps then you will be able to play in your lifetime. some of them are FAR more difficult then others.