well u got water team shouldn't be hard... first round burst the mobs down, 2nd round kill 1 asap then other 1 just normal atk till it die but do aware of it's overdrive timing(slow down for burst gauge)

when it comes to boss fight,
1. keep ur burst and only use it when boss is in raging mode(stunned it instantly, use belphe hydro to lower rage gauge + some skills if u not confident ur full burst can stun it)
2. use skills wisely(not when boss is stunned, u might wake him up too soon)
3. use belphe paralyze, increase stun duration
4. use nike def buff, belphe debuff and rusal reflect when overdrive is up