Nidalee - I could care less about spears, even with the debuff to heals you can sustain an entire team through most pokes by just maxing her E and stacking ap and cdr. It's insane when you can heal 45% of a squishy's lifetotal on a 5 second cd or what have you.
Xerath - he really needs a tank wall to be super oppressive, but if he has it game over.
His range can reach past tower while sitting in mid bush with locus of power on, and if you get a deathfire and Ionian boots, you have like a 2 second cd on locus of power. Good luck pushing a wave when xerath can just clear it safely from behind his own turret, while harassing/killing you with ult.
Also voidstaff + his passive is 62% spell pen. I hear thats good when you can spam a skill 3 times for 600 damage at around 1300 range on a 36 second cooldown.
Teemo - The reason surge is an op summoner spell. I've won every teemo game I've played on the back of surge, a blasting wand, an amp tome, and level 2 poison dart. No one expects than kind of damage out of teemo in the first teamfight, and it's disgusting how much cleanup power you have if you bait them to full engage by saving surge than popping t when they don't respect you damage.
Also , denying hp packs with mushrooms is completely doable with 34% cdr. In almost every case mushroom deals more dmg than an up pack gives, even if it's ad teemo, and even if they have tanks to pop them, usually they will take the hp anyways denying he squishes sustain.
Also, blind shuts down most of that fiora, akali, trynd **** where people go balls to the walls dive the pokers style.