Even the Japanese-themed Mystical Archive cards, which are mostly available only in Japanese booster packs, will be included in Collector Boosters of all languages
There are a lot of accessories that they sell as well, from Playmats to Sleeves, so it's always worth checking in and seeing if you can pick up some Japan limited items
A creature that enters the battlefield face up and turns face down later in the turn won't cause Tunnel Tipster's first ability to trigger
Metalcraft - Equipment you control have equip as long as you control three or more artifacts
Ratadrabik of Urborg is a great choice if Zombies will be attacking, and also to get more copies of legendary creatures like Sliver Gravemother
The controller wants to defeat the Siege, because once the Siege's last defense counter is removed, it is exiled, and its controller gets to play its reverse face for free