Tentacruel has a couple things going for itself. It has a nice typing of water/poison; has nice stats overall (it's a good bulky pokemon specifically) and as well has a good movepool (it's a nice rapid spinner/toxic spikes setter mainly) However, its design is just average in my opinion, and really it can be a little boring at times to use, so that is why I ranked Tentacruel here.
Note: This is my own personal ranking.
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