Hearthpwn

Even the worst 1-drops can become super good, with their effects, stats and cost multiplied by 5.

Examples:

Elven Archer 5 Mana 5/5 Deal 5 Damage

Stonetusk Boar 5 Mana 5/5 Charge

Leper Gnome 5 Mana 5/5  Deathrattle: Deal 10 Damage to the enemy hero

Lightwarden 5 Mana 5/10 Whenever a character is healed, gain +10 attack.

Anyone else with some ideas?

This just serves as a lesson on the non-linear mana curve.

You're not multiplying everything by 5.  The cost of cards is not just the mana cost; there's also the cost of the card itself.  To actually multiply it, you'd need to make it cost 5 cards rather than 1.  All of your seemingly over-powered examples start to look MUCH less over-powered when you add "Battlecry: Discard 4 cards" to them.

Quote from Asuryan >>

This just serves as a lesson on the non-linear mana curve.

Quote from Asuryan >>

You're not multiplying everything by 5.  The cost of cards is not just the mana cost; there's also the cost of the card itself.  To actually multiply it, you'd need to make it cost 5 cards rather than 1.  All of your seemingly over-powered examples start to look MUCH less over-powered when you add "Battlecry: Discard 4 cards" to them.

Red Mana Wyrm

Charge

After you play a Pirate, summon 5 copies of this minion from your deck

5/5

Kappa

PogChamp

Brann combo? PogChamp

Secret Keeper: 5/10 for every secret you play gain 5/5.

Kripp always says 1-drops are broken

Fiery Bat: 5 mana: 5 Attack, 4 Health. Deathrattle : deal 4 damage to a random enemy

Quote from Nellast >>

Fiery Bat: 5 mana: 5 Attack, 4 Health. Deathrattle : deal 4 damage to a random enemy

Because I can't post shit on imgur for a while:

Swashburglar: 5 mana 5/5 battlecry: add 5 random class cards to your hand (from your opponent's hand)

Big-Time Bucanneer: 5 mana 5/10 has +15 attack while you have a weapon

Furious Chicken: 5 mana 5/5 Enrage: +25 attack

Quote from vojza >>

Quote from Nellast >>

Fiery Bat: 5 mana: 5 Attack, 4 Health. Deathrattle : deal 4 damage to a random enemy

That's actually the most balanced one. 

Seems Balanced:

My favorit one would probably be:

Quote from Nellast >>

Fiery Bat: 5 mana: 5 Attack, 4 Health. Deathrattle : deal 4 damage to a random enemy

Shifter Zerus - 5 mana 5/5 Each turn this is in your hand, transform it into 5 random minions.

Worgen Infiltrator - 5 mana 10/5 Stealth.

Possessed Villager - 5 mana 5/5 Deathrattle: Summon a 5/5.

Lightning Bolt - 5 mana Deal 15 damage. Overload: 5

Goldshire Footman - 5 mana 5/10 Taunt.

Boom Bot - Deathrattle: Deal 5-20 damage to a random enemy.

Quote from SgtInvincibl >>

No, you cannot simply times things by 5.
 A one mana minion costs one mana and a card
 A five mana minion costs five mana and a card.

It does not cost 5 times as much so shouldnt be 5 times better

Quote from Maukiepaukie >>

Brann combo? PogChamp

Flame imp sounds ridicilous xD

 Shieldbearer would be sick with inner fire tho