There are two types of Surprise Bags that are available in-game during Tibia's 10th anniversary event.
Unfortunately, They are not available as drops by creatures anymore. This was discontinued by CipSoft at around the end of January, 2007. Finding one unopened in game is rare.
|Surprise Bag (Blue)||10.00 oz||None.|
<spoiler> You can get a Blue Surprise Bag through the Ultimate Challenges Quest. </spoiler>