Randomness
There are two kinds of randomness in the game: classic randomness and pooled randomness.
Classic randomness
Events occurring with classic randomness are happening with a given probability. They are denoted by a percentage (x%).
For instance, a 10% epic item drop rate means that, whenever an item drops, it has a 10% chance of being epic. There is no guarantee that after 10 item drops you will have one epic item. You may have zero, one or even more than one epic items (if you are lucky).
You can think of a 10-sided die being rolled whenever an item drops. If you roll a 1, the item is epic.
Known events with classic randomness:
- gear, jewel and soulstone drops from chests (item, tier and rarity - exception see below)
- random inventory item drops from gear chests (10% each)
- double meteorite drops
- critical gold drops
- critical hits and dodge
- mission running times (in a ±20% interval around the average)
- wave and stage skips
- guild expedition selection
- amulet activation
Pooled randomness
In contrast, some events are also occuring randomly, but with a guaranteed given rate. They are denoted by this rate (1 in x).
For instance, a 1 in 10 epic item drop rate means that in every 10 item drops exactly 1 item will be epic. In a given batch of 10 items, the epic item can be the first being dropped or the last or anywhere in between.
You can think of a pack of 10 cards, one being black and 9 being white. The pack is shuffled and, for each item you get, the top card is drawn. If the card is black, the item will epic. When the last card is drawn, the cards are shuffled back into a new pack.
Known events with pooled randomness:
- random gear chest drops from war missions (1 in 10 rare chest, 2 in 10 uncommon chest, 7 in 10 common chest)
- random scroll drops from adventure missions (10 in 30 scroll of speed, 10 in 30 scroll of damage, 10 in 30 scroll of health)
- appearance of a monster mission (1 in 3), naval mission (1 in 4), titan mission (1 in 4) or shadow mission (1 in 4) on the map
- new item drops from gear chests, jewel chests and celestial chests (rates depending on rarity)
- drops of legendary seals of power (1 in 10), mythic seals of power (1 in 15), titan seals of power (1 in 15) or angel seals of power (1 in 15) from gear, jewel and celestial chests
- appearance of a nebula chest (1 in 3), cosmic chest (1 in 4), galaxy chest (1 in 4) or stellar chest (1 in 4) in the oracle's rituals
- arcane conduit drops from jewel chests (3 in 22 per 11 components in the chest)
- tavern draws
- mystery box contents
- oracle's gifts contents
- weekly rewards