There's a glitch in the Arena. Some snakes in the desert get into melee range when autoattacking, and then I get locked into a loop where I only do 1 damage to the enemy every hit. The snake doesn't get knocked back far enough.
Invisible zebra gets hungry on every day but Friday. It eats 1000 xp on every day but Friday. If you feed it on Friday, then you gain 3% increase to your maximum boost. So, I've fed twice and I have 806% max.
Lag makes it unplayably sucky. I can handle some difficulty, but when I can't get the easy badge due to lag, then the game sucks. And that was with all of the extras turned down.