Sources:

Lock image: https://commons.wikimedia.org/wiki/File:Lock_font_awesome.svg (cc license)
Checkmark: https://en.wikipedia.org/wiki/File:Checkmark_green.svg (public domain)

Map: https://azgaar.github.io/Fantasy-Map-Generator/ (MIT license)

Coin: 2D Game Art Bundle - Casual Game UI - Purchased
    https://www.gamedevmarket.net/asset/2d-game-art-bundle-2018/ (royalty free)

Money, book, crown, cup, diamond, exit, flag_02, gem, gold, medal, prize, rank, skull_03, victory: Gui Icons - Purchased - https://www.gamedevmarket.net/asset/gui-icons-8656/ (royalty free)