Suggested by Eric Krillin’s a bit of a running joke among DBZ fans because his power level has always been a lot smaller than his allies. That being said, he is only relatively weak as he would be seen as a power house in most other series. He can easily destroy whole planets with a single blast and his speed is incredible. No matter how many elements Aang uses, he would simply not be able to catch Krillin and a single hit would be the end. Aang can’t overcome such a wide gap between these two. Krillin wins.
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did you even see any evidence of krillen destroying planets? and have you seen Aangs avatar state when he is 40+ years old in the LOK flashback? he is much more powerful then than when he fought Phoenix King Ozai.
Just look at his power level. Vegeta could destroy a planet at around 15-20000. Krillin surpassed that after having his potential unlocked and the power scaling does the rest. Aang is very strong, but I just don’t see him being able to keep up with Krillin.