FREAKIEST
FREAKY
bizarre, eccentric, freakish, freaky, flaky, flakey, gonzo, off-the-wall, outlandish, outre
(adjective) conspicuously or grossly unconventional or unusual; “restaurants of bizarre design--one like a hat, another like a rabbit”; “famed for his eccentric spelling”; “a freakish combination of styles”; “his off-the-wall antics”; “the outlandish clothes of teenagers”; “outre and affected stage antics”
freaky
(adjective) strange and somewhat frightening; “the whole experience was really freaky”
Source: WordNet® 3.1
Adjective
freakiest
superlative form of freaky: most freaky
Source: Wiktionary