While browsing the wiki i learned that minions were given snowballing in patch 5.23
NEW BUFF - PUSHING ADVANTAGE If your team's average level is higher than the enemy's: Your minions deal 10% bonus damage to enemy minions. If your team has taken more turrets, this damage is increased by a further 10%. Your minions take 1 + (turret differential × level differential) less damage (flat) from enemy minions.
If your average level is at least 3 levels higher and you've taken 2 more turrets in a single lane, your minions become Enraged: The bonus damage is increased by a further 90%. The flat damage reduction is increased by a further 7.
thoughts?