Btw, skills are fairly weak.
Skills are fairly weak on their own. Very few stand out as exceptions but there is one rule...
You NEED to step up.
Flame to Poison, Poison to flame, Oil to Flame, Flame to Oil
Water to Electricity, Poison to Water.
Chains + Armor, Decaying Touch + Healing.
Teleport + Battering Ram, Haste + Backstab.
The bigger issue right now is that some skills do not have strong combinations...
Water + Poison/Electricity is a huge scattershot that will backfire often. Though I will say it is a strong combination (electricity does full damage along the path)
Bows pretty much combo off of nothing, have no CC, and aren't too special damage wise. Their "Penetration" attack allows them to help, but for the most part Bows are ALL about the raw damage.
-HOWEVER! First Aid + Decaying Touch is the most powerful combination in the game... It is a boss slayer.
--As well special ammo (while too valuable a selling asset early on) is a game changer indeed.
Fire + Water, Air + Earth, Air + Fire, Necromancy + Fire: Are all unsupported combinations currently.
Earth and Necromancy are the only things that combo off of physical skills currently.
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Ultimately as I said... You NEED to combo.
I will say... Contamination and the fire version of it? Decent early game, but drop them.