For semi soft adhesive mastic use 120 grit sandpaper to remove it from the wall.
How to remove wall tile from drywall.
Put on protective gloves and place a piece of dry ice in a towel.
Then make and x motion within the tile with the tile cutter.
The method used to attach the tiles to the wall affects the way the tiles come off.
If the tile runs wall to wall proceed to step 2 to create your starting point.
The use of the right tools and materials combined with some elbow grease will remove most tile adhesives from drywall.
Fill drywall gouges with drywall joint compound and sand it smooth.
Score the 1st tile you plan on starting with using the grout cutter.
To remove thinset use a stiff putty knife and some elbow grease to scrape it from the wall.
Tap the handle of the tool with a hammer until the tile comes away from the wall.
This will further loosen the tile reducing the chances of you damaging the drywall behind it when you start removing the tile from the wall.
Fold the towel around the dry ice and twist the ends to give you a handle.
At the edge of the tile chip away the grout with the.
Removing tile adhesive from drywall is not an impossible process.
Allow to fully dry.
However it is unlikely that removing the adhesive will leave the drywall looking like new.
Hold the ice against the tile for a minute or two then try prying.
Give it a try by inserting a chisel putty knife or other flat tool in between the tile and the wall almost parallel to the wall.
Run the gout cutter around the tile edges in the grout area.
The extreme cold may make the glue brittle and cause the tile to come off easily.
If there is an outside edge to the tile you can start there.