So for example the mythic trickster.
Add your number of mythic charges to your dexterity or intelligence check.
You may "then" expend 1 blah blah blah.
What I want to know is, do we always add the number of mythic charges to relevant checks even if we don't intend on then expending them for D20's.
Its the part that says..... "you may 'then'".... Making it sound like you only add the number of mythic charges if you then intend to expend them.
Sorry if it's been answered already. Just a clarification.
The "then" for timing is to say if you had 3 charges and then spent 2 of them, you still get a +3 on the check you spent the charges on (e.g. you apply the bonus first, and THEN spend charges to bump dice to d20s -- if it was the other way around and the charges were spent first, then you'd get a smaller bonus which is not what is intended, hence the "then"). As The_Napier said, the static bonus applies to any checks using the listed skills regardless of whether or not you spend any charges on that check.