Topic already asks the question.
I always assumed kaioken is based only on fighting/attacking. A full supporter doesn't really need that though, do they?
its not a must to have but kaioken lvl 3 gives a nice attack bounus and kami's healing technique increases your heals based on your energy attack so it will give a nice bonus to your heal
ive seen a tw dende that heals 10k without kaio or rp and with kaioken and no rp increase his heals were 15k
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