Guardians and bosses
The last monster in each zone (★) is a guardian, and some are bosses. They have far more HP and defense than their level suggests and fight in a fixed pattern: a few attacks, a wind-up with a red cast bar before a heavy hit that can stun, then a short pause where they take 25% more damage. Below half HP they enrage: faster, harder hits and a new combo. Stuns and freezes interrupt a wind-up. The Monster tab spells out each pattern.
Action bar
Above the log: your first six active skills and four potion slots. Tap a skill to use it as soon as it's ready, or tap a potion to drink it now. Buff potions (Haste, Ironhide, Warding, Fury, Arcane) last 30s; set them in the Gear tab to drink automatically against guardians, in every fight, or only when tapped. Buy them in the Inventory shop.
Advanced jobs
At level 40 the job trial lets each class pick a branch. Knights choose Warlord, Dragoon (spear, pierces DEF, bleeds) or Berserker (axe, stacks speed, stronger at low HP). Wizards: Sorcerer or Hexer (stacking poison and burn). Rangers: Sharpshooter or Trapper (several traps, a hawk that attacks on its own). Rogues: Shadowblade or Duelist (double attacks, hits trigger skills). Clerics: Oracle or Templar (holy mace fighter, Smite on hit).
Trigger cards
Some cards say “chance on hit to cast a skill”. It fires for free with no SP cost and no cooldown, even if your hero doesn't know that skill. If you have learned it, it uses your skill level; otherwise it casts at level 5. Four-slot weapons have low attack but hold four cards, so four 5% cards add up to 20%.
Elemental reactions
Some elements hit harder on a target that is already affected, and skills that would set one off are used first. Shatter: wind hits a frozen target for 250% damage and ends the freeze. Toxic Burst: fire on a poisoned target deals the remaining poison damage at once, plus 25%. Glassed: earth hits leave the target Sandblasted for 6s, and the next fire hit deals 180% damage. Firestorm: wind on a burning target makes the burn 60% stronger and 3s longer.
Blacksmith
The Forge tab turns monster loot, ore and coins into weapons for every weapon type at levels 20, 45, 70 and 90. They're a little weaker than the best drops but always have 3 card slots, so you can reach the end game without lucky drops. Every monster's page lists exactly what it drops.