Ztank, /* internal tank/alien/bomb explosion */
Zeater, /* internal eater explosion */
Zdynamite, /* internal dynamite explosion */
+ Zboom, /* explosion */
+ Xchain, /* chain explosion; transition to Zboom */
Xboom_bug, /* bug explosion; transition to Zbug */
- Xboom_bomb, /* tank/alien/bomb explosion; transition to Ztank */
+ Xboom_tank, /* tank/alien/bomb explosion; transition to Ztank */
Xboom_android, /* android explosion; transition to Xboom_2 */
Xboom_1, /* tile explosion; transition to Xboom_2 */
Xboom_2, /* transition to boom[] */