It actually is a standard set now, but the cool thing about it is Magma Storm's trapping effect. If the opponent switches in and gets trapped, then they're helpless to stop you as you hit them with Solar Beam. This makes him harder to scout than other lures, who can be exposed by switching in a check and switching immediately back out again to scout for that "special" coverage move.Well that's the thing is that Trapper Tran is so anti meta. If it ever became standard it would completely lose its effectiveness because nobody would keep their bulky Waters in on it anymore. It's significantly easier to play around it if you know there's a decent chance your opponent is running it. It would completely lose its surprise factor.