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Ki (キリュク) is used to power magic-like effects, and is functionally comparable to mana. All restorative effects are permanent but boost effects are purely temporary and will run out very quickly. Ki fully restores when you sleep in your bed (and partially restores when using the Sleep Ki) so if you know you are going to return home soon you might as well use it up to make things easier.

Kana	Romaji	English	Level	Ki used	Effects
キアイ	Kiai	Scream	3	5	Restores 5 HP
タエル	Taeru	Endure	5	10	Defense +10
ハヤアルキ	Hayaaruki	Speedwalk	7	15	Speed +63
ナグル	Naguru	Strike	8	10	Attack +20
バクシン	Bakushin	Dash	12	15	Speed +127
フンバル	Fun'baru	Persist	15	20	Defense +35
ドキョウ	Dokyou	Guts	18	20	HP +32
サトリ	Satori	Enlightenment	20	10	Boost HP at the cost of Ki
ニラム	Niramu	Glare	21	25	Decreases each enemy's speed (random; usually from 7-11)
ネル	Neru	Sleep	24	1	Sleep to recover some HP and Ki. Can't sleep in some places.
ブンナグル	Bun'naguru	Knock	28	30	Attack +50
コンジョウ	Konjou	Temper	30	45	Restores 90 HP
ミキル	Mikiru	Escape	33	80	Defense +127
フットバス	Futtobasu	Full Power	35	100	Attack +127
アイノリ	Ainori	Ride Together	40	200	Increases Luck