Solved NullReferenceException with players in OnDeathEntity

Ohh..Please help me.
I try do Rank System, but have error:

Code:

(01:30:24) | [Oxide] 01:30 [Error] Failed to call hook 'OnEntityDeath' on plugin 'drank v0.1.0' (NullReferenceException: Object reference not set to an instance of an object)
(01:30:24) | [Oxide] 01:30 [Debug]   at Oxide.Plugins.Drank.OnEntityDeath (.BaseCombatEntity entity, .HitInfo info) [0x00000] in <filename unknown>:0
  at Oxide.Plugins.Drank.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x00000] in <filename unknown>:0
  at Oxide.Plugins.CSharpPlugin.InvokeMethod (HookMethod method, System.Object[] args) [0x00000] in <filename unknown>:0
  at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x00000] in <filename unknown>:0
  at Oxide.Core.Plugins.Plugin.CallHook (System.String name, System.Object[] args) [0x00000] in <filename unknown>:0

My code:

Code:

void OnEntityDeath(BaseCombatEntity entity, HitInfo info)
        {
            if(entity.ToPlayer())
            {
                BasePlayer player = BasePlayer.FindByID(entity.ToPlayer().userID);
                if(info.Initiator == player)
                {
                    UpSuicide(player);
                    return;
                }
                if (!info.Initiator.ToPlayer())
                {
                    UpDeath(player);
                    return;
                }
                else
                {
                    BasePlayer killer = BasePlayer.FindByID(info.Initiator.ToPlayer().userID);
                    UpDeath(player);
                    UpKill(killer);
                    return;
                }
            }
        }

If you death by player or suicide - normal. but if you die by Fall/bear/wolf - error...

 

But i check "if(entity.ToPlayer())" or don't it? I can't understend where i must check...
[DOUBLEPOST=1469836299][/DOUBLEPOST]

Code:

void OnEntityDeath(BaseCombatEntity entity, HitInfo info)
        {
            if(entity != null && entity is BasePlayer)
            {
                var player = entity as BasePlayer;
                var killer = info.Initiator as BasePlayer;
                if (killer == player)
                {
                    UpSuicide(player);
                    return;
                }
                if (killer == null)
                {
                    UpDeath(player);
                    return;
                }
                else
                {
                    UpDeath(player);
                    UpKill(killer);
                    return;
                }
            }
        }

I don't know how i did it. It's magic for me but it work. Solved.