Flexor the Mighty!
18/100 Strength!
The PHB gives a range of CL mods to modifiy the base 12/18 TN with, 1-5 for regular tasks, 6-10 for tough, etc. I'm not going to make ANY mechanics to cover any non stated activities, ability checks will handle all that. If it's something that is class related or I think a class would know make a attribute check and add your class level. If it's not make a check and don't add your class level. I'm going to wing most everything. I may make a list of common modifiers for reoccuring situations though. The last thing I want to do is add back in the things that I don't like about D20 fantasy games. Heck I'm glad to be rid of them.