Here is a list of controls and some useful information for Firebird's Sentinel.

S - turn left
D - turn right
L - look up
, - look down

T - create tree
B - create boulder
R - create robot
SPACE - cursor on/off
A - absorb tree/boulder/robot
Q - transfer to robot

H - hyperspace
U - turn 180 degrees
0 - pause (press 9 to return to the game)
1 - quit

On each level, you start near the bottom of the landscape and must reach the top
and absorb the Sentinel who stands on top of a pillar. To reach higher levels,
you create robots and transfer to them, and then absorb the old robot. However,
creating a robot requires 3 units of energy. You can also create boulders and
place a robot on top of them; 2 units of energy are required to create each
boulder. To obtain more energy, you can absorb trees, which will increase your
energy by 1 unit. Your energy is shown on the top left of the screen - a tree is
worth 1 unit, a boulder is worth 2 units, and a robot is worth 3 units. A gold
robot is worth 15 units.

While you are doing this, the Sentinel and his Sentries are rotating and
scanning the landscape for objects (including you!), and will absorb their
energy and create a tree at some other place on the landscape. An indicator at
the top right of the screen warns you if you are in the Sentinel's sights. If
you are, your energy will be reduced - you must move away as quickly as
possible. You can hyperspace to a random location, but this costs you 3 units of
energy.

When you have absorbed the Sentinel, press H to hyperspace to a new landscape.
Which landscape you are transferred to depends on how much energy you have
remaining.