Whenever a permanent other than a basic land enters, destroy all other permanents with that name
While removal can be annoying, make sure you pay close attention to any spells that let you access your graveyard to bring creatures or spells back into your hand.
Devote some resources to Sigarda and your plans are much better protected
During the night, cards with the nightbound keyword become more powerful
Starting with the Alara block, booster packs for both Core Sets and expansions began to contain 1 land, 10 commons, 3 uncommons, either 1 rare (7/8 chance) or 1 mythic rare (1/8 chance), and either a tip card (which explains the new rules in the set, such as exalted in the Alara Block or Infect in the Scars of Mirrodin Block) or a token (which is of a type produced by a card in the set)
There are plenty of other reasons, and I could go on and on