After a short grace period of difficulty increases very quickly and sharply and unlike eg FF VII or other newer parts, where you from the middle of the game through enstprechend good Summons, learned enemy techniques, etc. and simply the high with increasing level of damage output with normal opponents (and, unfortunately, most bosses) hardly has problems, it can happen in FF IV DS, that is consumed in the last third of the game from a (hochlevligen) standard Mob! There is tremendous understanding of the enemy weaknesses and strengths asked virtually every opponent during the game against at least half of all types of damage resistant or immune, spells and attacks the (five-member) party must be matched in part perfectly to a short time window (ATB / real-time battle system to use) in which the enemy is vulnerable or may be undermined in a state where auras / buffs, etc.
That in some tests the constant random battles were criticized, I can understand only partially (in the overall context). You MUST (!!) simply permanent level up to have even the slightest chance from the middle of the game (or earlier ..) to most bosses.
But that's what makes this game: looking levels, items and find tactical battles, and a feeling of happiness when one has once again cracked a boss (this also drop quite useful material times).
So I you do not want to spoil the fun, wiegesagt; for professionals and connoisseurs is the game is a real treasure, and confirmed once again something I never thought still time not too long ago: For young dependents Altzocker, Retro Fans (Wii Downloads) and Japanese-RPG fans are Nintendo's consoles currently first choice!