In game achievements and rewards

[Novir Vetru]

I want to make a list of achievements for a my players to try and achieve throughout the campaign. My goal is for the first one who completes the achievement, they will gain some boon or item either relevant to the task, or proportional to the difficulty of the task. Any tips for what tasks or rewards?

[Fero]

My GURPS group used to do this pretty regularly. One way we did it was to customize the task and reward to the character ("inflict at least 10 intelligent non humans with your terrible curse of were humanism"). Another variation was to keep the challenges secret but base them on tropes of the game setting ("regularly use a sound as a catchphrase" in a Scooby-Doo inspired game). For d&d I let everyone know the challenges and would use standard fantasy tropes mixed with some odd ball ones. Suggestions include: 1- Hold off a terrible evil on a bridge; 2- slay a dragon; 3- befriend a dragon; 4- redeem a villian; 5- ride a Unicorn; 6- walk into an obvious trap; 7- mary a goblin; 8- convince a construct of its own non-existance; 9- build a stronghold; 10- get caught naked in a combat encounter.

[Maat Mons]

Sell Soul to Fiend
Kill Another Player’s Character
Show Up More Than 30 Minutes Late to Game Night
Murder a Helpless Captive
Ritually Sacrifice a Peasant
Sell Own Party Out to BBEG
Steal from Party Member
Get Caught Cheating IRL
Aggravate King and Get Price on Head
Cause TPK via Stupidity
Burn Down Orphanage
Play a Kender

[Fero]

Sell Soul to Fiend
Kill Another Player’s Character
Show Up More Than 30 Minutes Late to Game Night
Murder a Helpless Captive
Ritually Sacrifice a Peasant
Sell Own Party Out to BBEG
Steal from Party Member
Get Caught Cheating IRL
Aggravate King and Get Price on Head
Cause TPK via Stupidity
Burn Down Orphanage
Play a Kender

I was nodding in agreement until you got to the last one. That is just evil.

[Gruftzwerg]

Maybe have a look into Touchstones from Sandstorm.

[Vaern]

Unearthed Arcana has a variant where feats are earned by performing certain actions. For example, dropping two enemies in melee on two consecutive turns might grant access to the cleave feat. Maybe do something like that, but only reward the bonus feat to the first character to achieve that requirement.

[Thurbane]

Would the Action Points (https://www.d20srd.org/srd/variant/adventuring/actionPoints.htm) variant work for this? Award bonus AP for certain in-game achievements?

Action Points are more fully fleshed out in various Eberron books, as well, including feats and PrCs that are focused on AP.