As in any RPG, much of your time in Triangle Strategy will be spent grinding. Simply completing the main scenario battles will not be enough to keep your units at a high level. However, there’s no way to find optional skirmishes around the map like other tactical RPGs, so you might be wondering where you’ll gain experience. Luckily, you don’t have to go too far out of the way.
Related: How to promote classes in Triangle Strategy
Choose your camp from the main menu. While here you will have access to various facilities such as the Blacksmith and the Miscellaneous Shop. Believe it or not, you’ll be looking for experience at this friendly home base.
After spawning in the camp, go right and talk to the Spirited bartender in the tavern. Talking to them gives you the option to select Mental Mock Battles. These are imaginary battle scenarios that will take you to different maps and put you in unique combat situations.
During your journey you will unlock more Mental Mock Battles. An early example puts you back from the beginning of the game in the Wolffort harbor, in the middle of two groups of enemies. Not only will this help you overcome pincer maneuvers, but it will also help you grind. The battles may be imaginary, but the experience your units gain is not. These Mental Mock Battles will also show you a recommended level requirement so you know if it is advisable to tackle that particular fight.
With triangle strategy, it’s important to remember that only your active units need to gain experience points and perform actions in battle to do so. If you put a low tier unit in a high tier Mental Mock Battle and leave them standing around, they gain nothing when the battle is over. Mental Mock Battles are a great way to level up commonly used units, and an even better way to ensure infrequently used units are leveling appropriately as well.
https://www.gamepur.com/guides/the-best-way-to-grind-experience-in-triangle-strategy The best way to gain experience in Triangle Strategy