Triara is easy to start and slow to master. Because combat plays itself out, your mistakes are invisible while you fight — they only show in the result. I have watched enough new games to notice that almost everyone trips over the same five things. None are serious, but fixing them changes a lot.
Mistake 1: not putting a real tank in the front
The front slot soaks most of the enemy's attention, because the engine prioritises the most forward target. If you put a mage or archer there "because they hit hard", they get deleted before they do anything. The front is for a knight or a warrior with resistance. It is rule number one and the one that fixes the most games at a stroke.
Mistake 2: spending all your action points on one thing
Action points are your limited daily resource, and exploration and hunting draw from the same pool. A lot of people burn it all exploring and then wonder why they have no pets. Split it: explore for materials and chests, but keep points for hunting. A team with no pets fights with one fewer body every battle.
Mistake 3: ignoring pets
Speaking of which: pets are not decoration. Each one adds another entity on the field and, above all, stats. A pet trained in agility dodges hits and buys your champion extra turns. If your team feels "squishy" and you cannot see why, it is almost always weak or missing pets, not bad champion stats.
Mistake 4: splitting the two skills with no plan
Each champion equips at most 2 skills, so every slot is a decision, not filler. The classic mistake is mixing one damage and one defence skill on the same champion "just in case", and ending up with a character that does nothing fully. It works better to specialise: let the damage dealer go for damage and the tank go for survival, and spread the roles across the team, not within one champion.
Mistake 5: jumping into the Arena without testing in exploration
The Arena has ELO: every avoidable loss costs ranking. Explorations, on the other hand, have predictable enemies and no penalty. They are the perfect test bench. If a new composition clears tough explorations without anyone dying, it is ready for the Arena. If it loses champions there, better it fails in exploration than in your ELO.
The common thread
All five mistakes share one root: treating Triara like a "whoever hits hardest wins" game instead of a preparation game. Since you do not touch anything during the fight, all the margin is beforehand: formation, resources, pets, skills, testing. If you want to go deeper into team theory, I have a team-building guide, and the class summary lives here. Once it clicks, the Arena is waiting.