Obstacles, items, and relics. From left to right,
Top row: Locked Door, Barred Door, Magic Door, Cracked Wall, Boulder, Obelisk
Middle row: Small Key, Switch, Roc's Feather, Bomb, Rupee, Power Glove
Bottom row: Heart Container, Cane of Somaria, Pit, Pegasus Boots, Chest, Lantern
Descriptions--
>Locked Doors can be opened with Small Keys
>Barred and Magic Doors can be opened by stepping on a Switch or passed through if the player has the Cane of Somaria relic.
>Cracked Walls and Boulders can be destroyed with Bombs.
>Boulders and Obelisks can be removed with the Power Glove relic.
>Rupees replace Gold, Lanterns replace Torches.
>The Heart Container is a relic and works like the Helmet of Protection.
>Pegasus Boots, also a relic, allow the player to move an extra space, somewhat like a permanent Lantern.
>>Pits: when a player is adjacent to a pit and wishes to cross, they must roll the dice. If a Shield or Sword is rolled, the player jumps the pit and proceeds to the next space. If a Skull or Skull/Sword is rolled, the player remains in place and loses 1 Health. If the player has the Roc's Feather relic, Pits may be jumped without rolling the dice.
Now, obviously these wouldn't all be in the same sets. Just like how different Heroica sets have doors and keys, magic doors, torches & rocks, etc., the different Zelda Heroica sets would have varying types of obstacles. Maybe one set would have lots of pits, and its relic would be Roc's Feather, and so on. You get the idea.