If you don't have it already,
here's a game from 1999 - Quake 3 Area Mac PPC:
http://www.myabandonware.com/game/quake-iii-arena-3p0#download
Hopefully your internet connection (& HDD) can handle a 542.4 MB zip archive.
Took me about 25 - 30 mins to download.
I'm guessing your Sawtooth can handle this game.
This FPS game wakes up one's lagging brain in the morning. Single player against game's AI.
Multiplayer option is included. Just to show you what the game looks like,
here's a brief YouTube video of someone playing it on an eMac:
Double-clicking on the zip file extracts the Quake 3 folder.
Inside are five game versions including MacQuake3 for Mac OS 9. Play the game right from the folder.
In my Sawtooth with Tiger, I double-clicked on the version "Quake3 10.2 G4" since it was named with "G4" (all guesswork on my part).
After boot-up splash screen, game asks for CD Key, but just leave it blank and click on Accept.
Next check out SETUP menu for CONTROLS, SYSTEM & GAME OPTIONS menus.
Don't need to config custom PLAYER menu just yet to play right away.
CONTROLS menu for movement are the usual [WSAD] keys (forward, back, step L, step R)
with Mouse for main turning direction. [SPACER] = jump, [C] = crouch.
Left mouse button for fire weapon. Familiar things to you already no doubt.
SYSTEM menu for Graphics, Display, Sound, Network (Multiplayer).
GAME OPTIONS menu for finer visual details on/off.
The game may be smart enough to sense a computer's playing limitations with presets.
Click BACK for main menu, then clicking SINGLE PLAYER gets you to CHOOSE LEVEL menu.
Leave present options as they are & click FIGHT to choose easy to hardest game playing skill.
Click BACK then SKIRMISH to begin fight between you the Unknown Player and "Crash", your opponent.
If killed, left mouse button respawns.
After first SKIRMISH, more fight locations with looked available, making an extra click or so then NEXT button to get in a fight.
The DEMOS menu contains only one recorded gameplay to watch.
The CINEMATICS menu lists ten videos (cut-scene or promo?) but only ID LOGO & INTRO are archived.
When you finally quit/exit game, [ESC] key closes the final credits if I remember correctly.