Shredder, Shadow Master

Although the token copies created by Shredder's first ability enter attacking, they were never declared as attacking creatures. Abilities that trigger whenever a creature attacks won't trigger when those tokens enter attacking.

If Shredder leaves the battlefield before his last ability resolves, the tokens will still enter as a copy of Shredder, using Shredder's copiable values from when he was last on the battlefield.

In the unusual case where Shredder becomes a copy of something else while his last ability is on the stack but before it resolves, the tokens will enter as a copy of whatever Shredder is copying.

The token copies will have Shredder's abilities.

The tokens don't copy whether Shredder is tapped or untapped, whether he has any counters on him or Auras attached to him, or any non-copy effects that have changed his types, color, and so on.