Being saved by Jesus Christ and inspired by his teachings he got from God myself and as a variant of a peaceful christian rogue-like, I'd propose this idea:
You're a Jesus Christ's disciple, going around cities and villages, preaching, baptizing in Jesus' name performing miracles - heal the sick and lepers, raise the dead and cast out devils, to make people believe in God, and give praise to God - since He gives you the powers, otherwise you won't be able to do
anything.
There are different powers: to speak different languages to convert foreigners, poison will not affect you, prophecies, invisibility to non-believers, dream visions with quests or warnings, destruction of idols. There are requirements as told by Jesus: you shouldn't take any money for your work, and you should immediately leave cities that wouldn't receive you; God won't like you mingle with non-believers.
The more you get faith from God, the more you'll be
tried by non-believers who will hate you and cause you mischief: being jailed, hit, stoned, tortured, thrown to animals, burned at the stake or crucified. A death like a martyr surely means immediate ascension into the kingdom of God. Sinning like don't do to others what you wouldn't like for yourself, lust, fornication, lies, judging people, hypocrisy, killing, stealing and other things God forbid reduces your faith and increases the chances you forget of God and become a false prophet without any powers. To clean sins you must repent; fasting provides increased effect, but people shouldn't see you fast or pray.
Good things like do to others what you'd like for yourself and conversion of non-believers increases your faith and cleans you of sins. You can also meet false prophets or magicians which you must convert or take away their false powers with God's miracles and prayer. People doing sins must be converted and asked for repentance, they also should not follow idols. People are converted better on seeing miracles. In some tough situations, God may send you angels, which are not winged men, to help you out or deliver you from death or jail. If you die like a martyr you win, given a position in God's kingdom according to your deeds; false prophets and unrepentant sinners go to hell, for eternal torture, but it's only for God to decide whoever goes where.
And that's all, it's what wisdom God has taught me, even if I am not a perfect christian, but good thing is he forgives the repentant. Perhaps the idea may not sound fun, but look closely at what humor/fun is - mostly things that God forbid; hacking/shooting people in games is fun, but in reality it's killing, insulting and judging other people is forbidden, sexual stuff is lust, slapstick is not what you'd like for yourself, jokes and anecdotes are commonly about lies and adultery; check for yourselves - it's everywhere in music, movies, books, etc. Though I'm not judging, I only tell what God has let me see, 'cause I didn't realize that myself.
I'm only talking about things that seem fun but are forbidden by God.
I'm also preaching here about God, because being even the smallest one in Heaven for ever, is INCOMPARABLY MUCH better that getting the biggest fan base with a rogue-like game, and attracting girls and getting proud by that fact for a tiny painful life.
Living by God's rules versus living by this world's rules is like peace versus war. Though if I did say something that Jesus didn't tell, don't believe me, believe him. Only through Jesus can one be saved, not through me.