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Grinder with a diamond blade.
That would be my first choice.
If you had to cut out a small shape on a tile that's already stuck on the wall you can carefully grind through the top layer with the grinder but you cn't sink the grinder blade right through the tile because the shape is too small.
What do you use to get the rest of the tile out? Drill and chip it out with a bolster?
It's not the kind of thing I do.
If the shape is circular, diamond hole saw might do it.
Airhead
Personally I would never use a multi tool to cut tiles. Grinder with a diamond blade.
In regards to multi tool blades I buy cheap ones now as the expensive one I found didn’t last much longer and we’re massively more than buying cheaper and throwing away