Still, I find Sudden Strike a bit overpowered. +3d6 (Sneak Attack 2d6 + Sudden Strike 1d6) damage for four times a day (assuming that they replenish Ki as Monks do, i.e. per short or long rest and they have a short rest per day) is too much for 3rd level. I’d make this cost 2 Ki in order to tone it down.

Also, Phase Through Walls is nice, but I’d make the character take force damage if trapped inside a solid object and return to the original position.

Explosive Ninja is awesome. Such a great idea and so many uses!!! If you use the Flanking optional rule it is explosive indeed, or if it is combined with other area controlling feats and powers. Do the five replicates start from the same spot you were in or within 5 feet of it? Is there a range in which each replicate must be? I’m asking because there are spells that can zap one replicate to a much further distance or even in an other plane. If the latter occurs, does the replicate perish and the original character lose HP?

The Feats are great. The Con Save of the Ground Fighter feat is against which DC?

The weapons list is really great.

All in all, with a few finishing touches, I can see a new Tribality Publishing product on the way!!!