Here is the full list of all 17 Sigi - there are A Fart for Melusina achievements.
There she goes again.
Defeat Ivan Stinkup.
Hard to find and almost out of reach.
Find the long lost golden crown.
An apple a day...
Defeat Kolles Terrol.
Kill 100 Zombies.
Defeat the Steel Horse.
Collect 1000 coins.
Defeat Blind John
Fart at Melusina.
Clear all caves.
Collect all SIGI's.
Find the long lost golden grail.
Find the long lost golden talisman.
In under 30 minutes?
Pocket 2500 coins.