The event bonus is a global bonus that used to change with events. Now it is commonly referred to as the weekly bonus and changes every week at Sunday's Daily Reset to a combination of two from this list:

Bonus Min Max Add/Multi
XP +10% +25% Multiplicative
Gold +10% +40% Multiplicative
Wood +10% +30% Additive
Stone +10% +20% Multiplicative
Fish Value +10% +40% Multiplicative
Cards +10% +40% Multiplicative
Crystals from Mining Always double
Pet Training Always double
Pet Points +10% +30% Multiplicative
Valor Always double
Expedition Points +10% +40% Multiplicative
Fishing Multicatch +10% +50% Additive

A bonus being additive or multiplicative relates to how that bonus works with the other bonuses in the game. This means that by nature, multiplicative bonuses tend to be much more powerful than additive bonuses.

The wood bonus is additive with the Ascension Upgrade Log Gains.

The "Crystals from Mining" bonus only apply to the crystals you get from mining.