start at token 1

src/Main.sol

@@ -222,12 +222,13 @@ contract Main is Owned {
     function sendBombs(uint256 _amount) external missionNotCompleted {
         // Ensure _amount will not exceed wallet balance of bombs, Unaboomer supply, and active Unaboomers
         uint256 supply = unaboomer.totalSupply();
+        uint256 killed = unaboomersKilled();
         require(_amount <= bombBalance(msg.sender), "not enough bombs");
         require(_amount <= supply, "not enough supply");
-        require(_amount <= supply - unaboomersKilled(), "not enough active boomers");
+        require(_amount <= supply - killed, "not enough active boomers");
         for (uint256 i; i < _amount; i++) {
-            // Pick a pseudo-random Unaboomer token
-            uint256 randomBoomer = uint256(keccak256(abi.encodePacked(i, _amount, block.timestamp, msg.sender))) % supply;
+            // Pick a pseudo-random Unaboomer token - imperfectly derives token IDs so that repeats are probable
+            uint256 randomBoomer = (uint256(keccak256(abi.encodePacked(i, _amount, killed, block.timestamp, msg.sender))) % supply) + 1;
             // Check if it was already killed
             bool dud = unaboomer.tokenDead(randomBoomer);
             // Kill it (does nothing if already toggled as dead)

src/Unaboomer.sol

@@ -94,18 +94,18 @@ contract Unaboomer is ERC721, Owned {
     /// Mint tokens from main contract
     /// @param _to Address to mint BOOMR tokens to
     /// @param _amount Amount of BOOMR tokens to mint
-    function radicalize(address _to, uint256 _amount) external payable onlyMain {
+    function radicalize(address _to, uint256 _amount) external onlyMain {
         require(totalSupply() + _amount <= MAX_SUPPLY, "supply reached");
         for (uint256 i; i < _amount; i++) {
-            _safeMint(_to, minted);
             minted++;
+            _safeMint(_to, minted);
         }
     }
 
     /// Toggle token state from living to dead
     /// @param tokenId Token ID of BOOMR to toggle living -> dead and increment kill count
     function die(uint256 tokenId) external onlyMain {
-        require(tokenId < totalSupply(), "invalid token id");
+        require(tokenId <= totalSupply(), "invalid token id");
         if (tokenDead[tokenId] == false) {
             totalKillCount++;
             tokenDead[tokenId] = true;