Hero Skill Slots: PVP
Hero skills are unlocked when the hero reaches sufficient experience level – 20, 60, and 100. The first slot is solely for an exclusive or supportive skill, whereas the next slots can be for unit (army/navy/air force) and supportive skills.
The most impactful skill is march size. This allows you to field more units. Critical early advice is that you should level these march size skills and place them in the first slot for your top heroes, rather than exclusive skills. The exclusive skill boxes are not sufficiently impactful to use until they reach level 4.
Rare march size cap skills are strongest, and you can also use normal march size caps in the next slots, particularly if you’ve been able to merge them to level 2, 3 or more.
The next most impactful skills are damage increase and damage decrease. These will typically more impactful than attack or HP, as damage is multiplicative, while attack/HP are additive. For example, +60% Attack when you already have +800% adds 860/800 = 7.5%. Attack and HP are typically used thereafter.
Managing your skills can unfortunately be time consuming, as there is no easy way to merge all. Most normal skills are also useless and should be disassembled for skill chips – except for normal march size, gold production and maybe march speed for Diana/Bob.
There are a few noteworthy exceptions to the rule on exclusive skill boxes. For a few heros, the level 3 exclusive skill is particularly useful because it begins offering a second benefit, beyond the typical improvement of hero skill:
Current Exclusive Skills level 3/5/7
Training speed Navy 15/30/60%: Merida
Training speed Air 15/30/60%: Lady Zizak
Gathering Speed 15/30/60%: Ganso/Tywin
Air vs Air DMG Inc 10/20/40%: Tian Mu
Army DMG Inc 10/20/40%: Bradley
Skills level up to 10, which would be tremendously expensive to achieve (19,683 individual skills at 10). 81 skills merge to a level 5, and multiply by 3 for each level beyond that.
Other Uses for Skill Slots
For non PVP specialty heros, certain supportive skills can be helpful. For Diana and Bob, who should be set as a preset for grinding warhammers and dark forces, march speed is a useful skill. Gatherers like Black Widow and Kate Curry should use resource gathering speed skills, and oil or food speed.
In addition, gold production increase is a very useful skill. Placing it on a hero provides a buff to your overall gold production. For those looking to optimize, you can get a meaningful bonus by placing this on heros you are not actively using – think Sam, or Teresa, or O’Neill. By leveling these heros exp level up to 20, you can then place a normal and rare skill on them – with rare and normal, this will boost your gold production by 3.5% each time.