pokemon black fourth gym help?

i recemend making your strongest pokemon 2 lvls higher than her strongest (so lvl 29). Then I make the rest of my pokemon around the same lvl as her other pokemon (so lvl 25). Also if you can teach sandile dig instead of mud slap. Teach victini Flame Charge instead of incinerate. Teach sawk work up instead of low kick (there are not that many heavy pokemon so its not that good). Teach servine mega drain instead of vine whip. Also teach yamask omnious wind instead of haze. Also i recommend getting rid of darumaka considering you already have a fire type (victini). Instead get a flying type like unfezant or sigilyph. Hope this helped :)