You could try a 3-Heart challenge on one of the Legend of Zelda games. Or battletoads or Dragon's Lair (NES).
Be sure to suggest challenge runs of stuff too! Nothing quite beats the rage of Professional Resident Evil 5 with only unupgraded pistols for weapons.
Bioshock Infinite on 1999 mode without using Dollar Bills. You don't have to beat the game for 1999, you can actually put in the Konami Code and it unlocks it.
I did that a few days ago. I didn't use the dollar bill machines for a good majority of the game and just decided to not use them at all.
Run through any Halo that has skulls with all skulls on and on Legendary You toke that idea from that achievement/trophy, didn't you? EDIT: Another idea: Play Starfox Assault, Every time someone calls for help or when R.O.B demands a maneuver, DRINK. (Drink preferred to be alcoholic, can be substituted for a mixture of at least 3 different flavored carbonated beverages.)
I know Zephyr will love this one... LET'S GET SERIOUS (Sam) If you think that would be too easy, then do pistol/dual pistol only run! And for Ramza... SOUL CALIBUR 5 Only use kicks! Only use low attacks! Hmm... other suggestions will come! EDIT: That didn't take long >.> If you haven't played it, Syoban Action. And I know Ramza has Chivalry, so I put it to him to play only using his fists!
Dota 2 Dota 2 Dota 2 Guild Wars 2 (Go WvW as a low level character, I dare ya) Dota 2 Bioshock Infinite babyyyyy Half Life 2 babyyyyy For Dota 2, have only hard supports. No carries.
If your still looking for an idea, you could try and do a retro game gauntlet: http://vgauntlet.wikia.com/wiki//v/_Gauntlet_Wiki Or if your just looking for single games, this site is more helpful: http://s3kr.it/gauntlet.html
