Dungeon Story: Match and Monsters is a match-3 dungeon crawler where you can go on runs, defeating enemies (and bosses) before dying and returning to your town. There, you can purchase upgrades, train up your level, or unlock new characters before going back in.
A lot of games on mobile have match-3 elements, which are often challenging and involve a lot of trying to clear things. Dungeon Story uses match-3 to actually do your attacks, gain money, and refresh your health. When fighting in dungeons, the majority of the screen is a grid of match-3 icons, with a small inventory at the bottom. When it's your turn, you can select one of the three icons and match 3 or more to do your turn.
If you match hearts, you will be gaining health; if you match coins, you will get coins; and if you match swords, you will do damage.

One thing I really like about the matching element here is that as you are dragging your line across, you are actually seeing how much damage will be pulled off of the enemy's health bar.
This can help you not use up more swords than needed. The same is done with your health, so that you can leave some on the board for the next turn. This sort of view, and thinking ahead, often had me looking to destroy monsters in one single hit (unless they were bosses), and otherwise, I managed my health and coins.
There is a good variety of enemies in Dungeon Story: Match and Monsters, from bugs that can poison you, to simple swordsmen and skeletons, to larger bosses like tree-monsters. The bosses do have a warning when they come on and often cannot be killed in a single hit, but they are well worth destroying as they give out fragments that unlock more areas to fight in when you have enough of them.
Back at the map in Dungeon Story, you can then decide what to do with all of your loot. Spending coins can upgrade your items at the merchants, or if you have a lot of coins, you can get an inventory item that holds some power (like a revive, so you can keep fighting forward when you die in the dungeon or a potion to help you survive without wasting a turn).
You can also battle some monsters to level up, where you can end at any point in the training ground. Purchasing new heroes, which are far more powerful than the past ones, is done through skulls. These skulls are only earned by fighting monsters and skulls, so they are quite rare.
You can then go back into battle and try again! It's quite moreish, going back into the dungeon and facing off against another string of monsters. I kind of like that there isn't some goal with each level, and that instead I can just play through, only losing when I come up against a monster that is much stronger than me.