minor adjustments

src/UnaboomerCommon.sol

@@ -10,10 +10,7 @@ BOMB holders can randomly mail bombs to other owners
 chaos ensues until 1000 survivors - the game stops
 ********/
 
-import {ERC721} from "solmate/tokens/ERC721.sol";
 import {Owned} from "solmate/auth/Owned.sol";
-import {LibString} from "solmate/utils/LibString.sol";
-
 import {Unaboomer} from "./Unaboomer.sol";
 import {Mailbomb} from "./Mailbomb.sol";
 
@@ -60,8 +57,11 @@ contract UnaboomerCommon is Owned {
     //                              Modifiers
     // =========================================================================
 
-    modifier missionCompleted {
-        require(unaboomer.killCount() <= unaboomer.SURVIVOR_COUNT(), "mission already completed");
+    modifier missionNotCompleted {
+        require(
+            unaboomer.killCount() <= (unaboomer.MAX_SUPPLY() - unaboomer.SURVIVOR_COUNT()), 
+            "mission already completed"
+        );
         _;
     }
 
@@ -69,26 +69,24 @@ contract UnaboomerCommon is Owned {
     //                              Tokens
     // =========================================================================
 
-    /// Radicalize a boomer to become a Unaboomer
-    function radicalizeBoomers(uint256 _amount) external payable missionCompleted {
-        // check if game halted
+    /// Radicalize a boomer to become a Unaboomer - start with 2 bombs
+    function radicalizeBoomers(uint256 _amount) external payable missionNotCompleted {
         require(msg.value >= _amount * boomerPrice, "not enough ether");
         unaboomer.mint(msg.sender, _amount);
         mailbomb.mint(msg.sender, _amount * 2);
     }
 
     /// Assemble additional mailbombs to kill targets
-    function assembleBombs(uint256 _amount) external payable missionCompleted {
-        // check if game halted
+    function assembleBombs(uint256 _amount) external payable missionNotCompleted {
         require(msg.value >= _amount * bombPrice, "not enough ether");
         mailbomb.mint(msg.sender, _amount);
     }
 
-    /// Send N bombs to pseudo-random Unaboomer tokenIds to potentially kill them.
-    /// If the Unaboomer is already dead, the bomb is a dud.
+    /// Send N bombs to pseudo-random Unaboomer tokenIds to kill them.
+    /// If the Unaboomer is already dead, the bomb is considered a dud.
     /// @dev Pick a pseudo-random tokenID from Unaboomer contract and toggle a mapping value  
     /// @dev The likelihood of killing a boomer decreases as time goes on - i.e. more duds
-    function sendBombs(uint256[] calldata tokenIds) external missionCompleted returns (bool[] memory results) {
+    function sendBombs(uint256[] calldata tokenIds) external missionNotCompleted returns (bool[] memory results) {
         require(tokenIds.length <= mailbomb.balanceOf(msg.sender));
         bool[] memory res = new bool[](tokenIds.length);
         uint256 boomerSupply = unaboomer.totalSupply();