The Grand Marshall was an Ice Warrior officer that led the attack on T-Mat Control in the 21st century.
- You may be looking for another Grand Marshall.
He was similar in appearance to Ice Lord Slaar, although he wore a more ornate helmet. He spoke normally (rather than the hoarse, loud whispers used by some Ice Warriors), as he was in "his own atmosphere".
He was killed, along with the rest of his Ice Warrior fleet, when Slaar's homing beacon was hijacked by the Second Doctor, sending them crashing into the Sun. (TV: The Seeds of Death)