Changes

|example= You may make a DC 15 + the equivalent spell level of the invocation you wish to learn will save. Regardless of On success you learn the invocation for a number of hours equal to your casting ability score bonus. However when forcing yourself to learn an invocation if you fail the will , on a failed save you don't learn and take 1d3 constitution damage that can only be healed from through natural rest. On success you don't take constitution damage. If you force yourself to learn more invocations then just one the DC increases by 5 each timeyou do so, the DC goes down by 5 for each invocation you forget. You can only learn invocations that you would already be able to meet the caster level for.