When something stops you
Sooner or later something in Tales of Varden stops you dead: a dungeon final boss, a tower floor, an arena opponent you should apparently beat. Because combat resolves from what you brought, a wall is never bad luck and never a skill issue. It is a specific missing thing, and the useful response is to work out which one rather than to run it again.
Running it again is the response the game makes easiest and it is almost always the worst one, which is why this guide exists.
Read the fight before changing anything
Watch which round the fight turned, because the answer is different for each case. If you died early, you have a survivability problem and no amount of damage fixes it. If you were ahead and then lost, the enemy outlasted you: that is attrition, and the answers are healing, mitigation, or ending it faster. If neither of you was getting anywhere, your damage is not landing, which usually means armor or resistance rather than a low damage number.
That third case is the one most often misread. A build that hits hard everywhere else and does nothing to one particular enemy has met armor, and the fix is penetration or an armor-ignoring effect, not bigger numbers. The tavern is the cheap place to confirm a theory - a contract is a known repeatable opponent, so you can test a change there without spending a dungeon cooldown on it.
The five levers, cheapest first
First, your pet, because it is free and it is the biggest single swing available: an element that answers the specific failure above will do more than several gear upgrades. Second, a potion, which is the only pre-fight choice in the game that is not permanent and is therefore worth brewing against a named obstacle rather than in general. Third, finish a set - a completed lower-rarity set beats mismatched better pieces, and this is the cheapest real power increase most characters have available.
Fourth, the smith, which scales every line on an item and is worth spending on a piece you intend to keep. Fifth, and only fifth, more levels. Levels are the slowest lever and the one players reach for first, which is why walls take longer to clear than they need to.
Why re-running is the worst option
A fight lost by a small margin reads as one lucky round from a win, and that impression is what turns an evening into a losing streak. It is also usually wrong: the same two builds fighting again produce approximately the same fight, and the variance you are hoping for is smaller than the gap you are trying to close. Dungeon runs sit behind a cooldown, so a re-run is not free even when it feels like it.
Two losses in a row is the point to stop and change something. The change does not have to be big - a pet swap costs nothing - but it has to be a change, because the third identical attempt is the first genuinely wasted one.
When the answer is somewhere else entirely
Dungeon difficulty comes from one number that climbs with the tier, and the step between tiers is a large fraction of the gap between dungeons. That means the mid tiers of your current dungeon are harder than the opening tiers of the next one, so a wall at tier seven is frequently a signal to go and open the dungeon above rather than to keep grinding this one. You come back with the gear it dropped.
The same logic covers the tower, which does not reset and can be left for a day, and the arena, where a stall is a matchup gap rather than a power gap. If your build has no answer to healing or no way through armor, it can farm perfectly well and still sit still on the ladder, and the fix is a counter rather than another week of levels.