I can not seem to get the Detection modes to work, I can give a player Feel Tremor and he can “see” the mobs, but when I click the Invisibility icon on the tokens they vanish. See/Sense invisibility will not allow me to see the tokens, see/sense all doesn’t allow me to see the tokens, feel Tremor stops working as well. It is like the invisibility option on the tokens completely overrides all of the detection modes.
is there another way to apply invisibility so that the detections will see them?
Unfortunately, the behaviour of this can vary quite a lot between different systems and with modules enabled or disabled.
Some systems will have special rules for invisibility.
To explain what I mean, here are a few screenshots from
pf2e which uses visibility mechanics that are designed to work with the detection modes.
And here’s a player character with blind fight and two enemies. Both are invisible, but the one on the right is also toggled to not visible by the GM, which makes it undetectable.
If you are playing dnd5e specifically, make sure that the player’s token has the right Detection Mode configured, as this may not be automated by spell effects.